| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							itsclquadb.q | 
							 |-  Q = ( ( A ^ 2 ) + ( B ^ 2 ) )  | 
						
						
							| 2 | 
							
								
							 | 
							itsclquadb.t | 
							 |-  T = -u ( 2 x. ( B x. C ) )  | 
						
						
							| 3 | 
							
								
							 | 
							itsclquadb.u | 
							 |-  U = ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) )  | 
						
						
							| 4 | 
							
								
							 | 
							simpl1 | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ x e. RR ) -> ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) )  | 
						
						
							| 5 | 
							
								
							 | 
							simp2 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> R e. RR+ )  | 
						
						
							| 6 | 
							
								5
							 | 
							adantr | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ x e. RR ) -> R e. RR+ )  | 
						
						
							| 7 | 
							
								
							 | 
							simp3 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> Y e. RR )  | 
						
						
							| 8 | 
							
								7
							 | 
							anim1ci | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ x e. RR ) -> ( x e. RR /\ Y e. RR ) )  | 
						
						
							| 9 | 
							
								1 2 3
							 | 
							itscnhlc0yqe | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ ( x e. RR /\ Y e. RR ) ) -> ( ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) -> ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) )  | 
						
						
							| 10 | 
							
								4 6 8 9
							 | 
							syl3anc | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ x e. RR ) -> ( ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) -> ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) )  | 
						
						
							| 11 | 
							
								10
							 | 
							rexlimdva | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( E. x e. RR ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) -> ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) )  | 
						
						
							| 12 | 
							
								
							 | 
							simp3 | 
							 |-  ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) -> C e. RR )  | 
						
						
							| 13 | 
							
								12
							 | 
							3ad2ant1 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> C e. RR )  | 
						
						
							| 14 | 
							
								
							 | 
							simp2 | 
							 |-  ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) -> B e. RR )  | 
						
						
							| 15 | 
							
								14
							 | 
							3ad2ant1 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> B e. RR )  | 
						
						
							| 16 | 
							
								15 7
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( B x. Y ) e. RR )  | 
						
						
							| 17 | 
							
								13 16
							 | 
							resubcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C - ( B x. Y ) ) e. RR )  | 
						
						
							| 18 | 
							
								
							 | 
							simp11l | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> A e. RR )  | 
						
						
							| 19 | 
							
								
							 | 
							simp11r | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> A =/= 0 )  | 
						
						
							| 20 | 
							
								17 18 19
							 | 
							redivcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C - ( B x. Y ) ) / A ) e. RR )  | 
						
						
							| 21 | 
							
								20
							 | 
							adantr | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( C - ( B x. Y ) ) / A ) e. RR )  | 
						
						
							| 22 | 
							
								
							 | 
							oveq1 | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( x ^ 2 ) = ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) )  | 
						
						
							| 23 | 
							
								22
							 | 
							oveq1d | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) )  | 
						
						
							| 24 | 
							
								23
							 | 
							eqeq1d | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) <-> ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) ) )  | 
						
						
							| 25 | 
							
								
							 | 
							oveq2 | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( A x. x ) = ( A x. ( ( C - ( B x. Y ) ) / A ) ) )  | 
						
						
							| 26 | 
							
								25
							 | 
							oveq1d | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( ( A x. x ) + ( B x. Y ) ) = ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) )  | 
						
						
							| 27 | 
							
								26
							 | 
							eqeq1d | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( ( ( A x. x ) + ( B x. Y ) ) = C <-> ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = C ) )  | 
						
						
							| 28 | 
							
								24 27
							 | 
							anbi12d | 
							 |-  ( x = ( ( C - ( B x. Y ) ) / A ) -> ( ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) <-> ( ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = C ) ) )  | 
						
						
							| 29 | 
							
								28
							 | 
							adantl | 
							 |-  ( ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) /\ x = ( ( C - ( B x. Y ) ) / A ) ) -> ( ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) <-> ( ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = C ) ) )  | 
						
						
							| 30 | 
							
								17
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C - ( B x. Y ) ) e. CC )  | 
						
						
							| 31 | 
							
								18
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> A e. CC )  | 
						
						
							| 32 | 
							
								30 31 19
							 | 
							sqdivd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) = ( ( ( C - ( B x. Y ) ) ^ 2 ) / ( A ^ 2 ) ) )  | 
						
						
							| 33 | 
							
								13
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> C e. CC )  | 
						
						
							| 34 | 
							
								16
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( B x. Y ) e. CC )  | 
						
						
							| 35 | 
							
								
							 | 
							binom2sub | 
							 |-  ( ( C e. CC /\ ( B x. Y ) e. CC ) -> ( ( C - ( B x. Y ) ) ^ 2 ) = ( ( ( C ^ 2 ) - ( 2 x. ( C x. ( B x. Y ) ) ) ) + ( ( B x. Y ) ^ 2 ) ) )  | 
						
						
							| 36 | 
							
								33 34 35
							 | 
							syl2anc | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C - ( B x. Y ) ) ^ 2 ) = ( ( ( C ^ 2 ) - ( 2 x. ( C x. ( B x. Y ) ) ) ) + ( ( B x. Y ) ^ 2 ) ) )  | 
						
						
							| 37 | 
							
								13
							 | 
							resqcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C ^ 2 ) e. RR )  | 
						
						
							| 38 | 
							
								37
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C ^ 2 ) e. CC )  | 
						
						
							| 39 | 
							
								
							 | 
							2re | 
							 |-  2 e. RR  | 
						
						
							| 40 | 
							
								39
							 | 
							a1i | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> 2 e. RR )  | 
						
						
							| 41 | 
							
								13 16
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C x. ( B x. Y ) ) e. RR )  | 
						
						
							| 42 | 
							
								40 41
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( C x. ( B x. Y ) ) ) e. RR )  | 
						
						
							| 43 | 
							
								42
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( C x. ( B x. Y ) ) ) e. CC )  | 
						
						
							| 44 | 
							
								38 43
							 | 
							negsubd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + -u ( 2 x. ( C x. ( B x. Y ) ) ) ) = ( ( C ^ 2 ) - ( 2 x. ( C x. ( B x. Y ) ) ) ) )  | 
						
						
							| 45 | 
							
								15
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> B e. CC )  | 
						
						
							| 46 | 
							
								7
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> Y e. CC )  | 
						
						
							| 47 | 
							
								33 45 46
							 | 
							mulassd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C x. B ) x. Y ) = ( C x. ( B x. Y ) ) )  | 
						
						
							| 48 | 
							
								47
							 | 
							eqcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C x. ( B x. Y ) ) = ( ( C x. B ) x. Y ) )  | 
						
						
							| 49 | 
							
								48
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( C x. ( B x. Y ) ) ) = ( 2 x. ( ( C x. B ) x. Y ) ) )  | 
						
						
							| 50 | 
							
								
							 | 
							2cnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> 2 e. CC )  | 
						
						
							| 51 | 
							
								13 15
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C x. B ) e. RR )  | 
						
						
							| 52 | 
							
								51
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C x. B ) e. CC )  | 
						
						
							| 53 | 
							
								50 52 46
							 | 
							mulassd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( 2 x. ( C x. B ) ) x. Y ) = ( 2 x. ( ( C x. B ) x. Y ) ) )  | 
						
						
							| 54 | 
							
								53
							 | 
							eqcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( ( C x. B ) x. Y ) ) = ( ( 2 x. ( C x. B ) ) x. Y ) )  | 
						
						
							| 55 | 
							
								33 45
							 | 
							mulcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( C x. B ) = ( B x. C ) )  | 
						
						
							| 56 | 
							
								55
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( C x. B ) ) = ( 2 x. ( B x. C ) ) )  | 
						
						
							| 57 | 
							
								56
							 | 
							oveq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( 2 x. ( C x. B ) ) x. Y ) = ( ( 2 x. ( B x. C ) ) x. Y ) )  | 
						
						
							| 58 | 
							
								49 54 57
							 | 
							3eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( C x. ( B x. Y ) ) ) = ( ( 2 x. ( B x. C ) ) x. Y ) )  | 
						
						
							| 59 | 
							
								58
							 | 
							negeqd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> -u ( 2 x. ( C x. ( B x. Y ) ) ) = -u ( ( 2 x. ( B x. C ) ) x. Y ) )  | 
						
						
							| 60 | 
							
								59
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + -u ( 2 x. ( C x. ( B x. Y ) ) ) ) = ( ( C ^ 2 ) + -u ( ( 2 x. ( B x. C ) ) x. Y ) ) )  | 
						
						
							| 61 | 
							
								44 60
							 | 
							eqtr3d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) - ( 2 x. ( C x. ( B x. Y ) ) ) ) = ( ( C ^ 2 ) + -u ( ( 2 x. ( B x. C ) ) x. Y ) ) )  | 
						
						
							| 62 | 
							
								45 46
							 | 
							sqmuld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( B x. Y ) ^ 2 ) = ( ( B ^ 2 ) x. ( Y ^ 2 ) ) )  | 
						
						
							| 63 | 
							
								61 62
							 | 
							oveq12d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) - ( 2 x. ( C x. ( B x. Y ) ) ) ) + ( ( B x. Y ) ^ 2 ) ) = ( ( ( C ^ 2 ) + -u ( ( 2 x. ( B x. C ) ) x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) )  | 
						
						
							| 64 | 
							
								15 13
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( B x. C ) e. RR )  | 
						
						
							| 65 | 
							
								40 64
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( B x. C ) ) e. RR )  | 
						
						
							| 66 | 
							
								65
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( 2 x. ( B x. C ) ) e. CC )  | 
						
						
							| 67 | 
							
								66 46
							 | 
							mulneg1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( -u ( 2 x. ( B x. C ) ) x. Y ) = -u ( ( 2 x. ( B x. C ) ) x. Y ) )  | 
						
						
							| 68 | 
							
								2
							 | 
							eqcomi | 
							 |-  -u ( 2 x. ( B x. C ) ) = T  | 
						
						
							| 69 | 
							
								68
							 | 
							oveq1i | 
							 |-  ( -u ( 2 x. ( B x. C ) ) x. Y ) = ( T x. Y )  | 
						
						
							| 70 | 
							
								69
							 | 
							a1i | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( -u ( 2 x. ( B x. C ) ) x. Y ) = ( T x. Y ) )  | 
						
						
							| 71 | 
							
								67 70
							 | 
							eqtr3d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> -u ( ( 2 x. ( B x. C ) ) x. Y ) = ( T x. Y ) )  | 
						
						
							| 72 | 
							
								71
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + -u ( ( 2 x. ( B x. C ) ) x. Y ) ) = ( ( C ^ 2 ) + ( T x. Y ) ) )  | 
						
						
							| 73 | 
							
								72
							 | 
							oveq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + -u ( ( 2 x. ( B x. C ) ) x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) = ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) )  | 
						
						
							| 74 | 
							
								36 63 73
							 | 
							3eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C - ( B x. Y ) ) ^ 2 ) = ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) )  | 
						
						
							| 75 | 
							
								74
							 | 
							oveq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C - ( B x. Y ) ) ^ 2 ) / ( A ^ 2 ) ) = ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 76 | 
							
								32 75
							 | 
							eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) = ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 77 | 
							
								
							 | 
							resqcl | 
							 |-  ( Y e. RR -> ( Y ^ 2 ) e. RR )  | 
						
						
							| 78 | 
							
								77
							 | 
							recnd | 
							 |-  ( Y e. RR -> ( Y ^ 2 ) e. CC )  | 
						
						
							| 79 | 
							
								78
							 | 
							3ad2ant3 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( Y ^ 2 ) e. CC )  | 
						
						
							| 80 | 
							
								18
							 | 
							resqcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( A ^ 2 ) e. RR )  | 
						
						
							| 81 | 
							
								80
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( A ^ 2 ) e. CC )  | 
						
						
							| 82 | 
							
								
							 | 
							recn | 
							 |-  ( A e. RR -> A e. CC )  | 
						
						
							| 83 | 
							
								
							 | 
							sqne0 | 
							 |-  ( A e. CC -> ( ( A ^ 2 ) =/= 0 <-> A =/= 0 ) )  | 
						
						
							| 84 | 
							
								82 83
							 | 
							syl | 
							 |-  ( A e. RR -> ( ( A ^ 2 ) =/= 0 <-> A =/= 0 ) )  | 
						
						
							| 85 | 
							
								84
							 | 
							biimpar | 
							 |-  ( ( A e. RR /\ A =/= 0 ) -> ( A ^ 2 ) =/= 0 )  | 
						
						
							| 86 | 
							
								85
							 | 
							3ad2ant1 | 
							 |-  ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) -> ( A ^ 2 ) =/= 0 )  | 
						
						
							| 87 | 
							
								86
							 | 
							3ad2ant1 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( A ^ 2 ) =/= 0 )  | 
						
						
							| 88 | 
							
								79 81 87
							 | 
							divcan2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) x. ( ( Y ^ 2 ) / ( A ^ 2 ) ) ) = ( Y ^ 2 ) )  | 
						
						
							| 89 | 
							
								88
							 | 
							eqcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( Y ^ 2 ) = ( ( A ^ 2 ) x. ( ( Y ^ 2 ) / ( A ^ 2 ) ) ) )  | 
						
						
							| 90 | 
							
								76 89
							 | 
							oveq12d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) + ( ( A ^ 2 ) x. ( ( Y ^ 2 ) / ( A ^ 2 ) ) ) ) )  | 
						
						
							| 91 | 
							
								81 79 81 87
							 | 
							divassd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( A ^ 2 ) x. ( Y ^ 2 ) ) / ( A ^ 2 ) ) = ( ( A ^ 2 ) x. ( ( Y ^ 2 ) / ( A ^ 2 ) ) ) )  | 
						
						
							| 92 | 
							
								91
							 | 
							eqcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) x. ( ( Y ^ 2 ) / ( A ^ 2 ) ) ) = ( ( ( A ^ 2 ) x. ( Y ^ 2 ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 93 | 
							
								92
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) + ( ( A ^ 2 ) x. ( ( Y ^ 2 ) / ( A ^ 2 ) ) ) ) = ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) + ( ( ( A ^ 2 ) x. ( Y ^ 2 ) ) / ( A ^ 2 ) ) ) )  | 
						
						
							| 94 | 
							
								65
							 | 
							renegcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> -u ( 2 x. ( B x. C ) ) e. RR )  | 
						
						
							| 95 | 
							
								2 94
							 | 
							eqeltrid | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> T e. RR )  | 
						
						
							| 96 | 
							
								95 7
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( T x. Y ) e. RR )  | 
						
						
							| 97 | 
							
								37 96
							 | 
							readdcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + ( T x. Y ) ) e. RR )  | 
						
						
							| 98 | 
							
								15
							 | 
							resqcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( B ^ 2 ) e. RR )  | 
						
						
							| 99 | 
							
								7
							 | 
							resqcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( Y ^ 2 ) e. RR )  | 
						
						
							| 100 | 
							
								98 99
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( B ^ 2 ) x. ( Y ^ 2 ) ) e. RR )  | 
						
						
							| 101 | 
							
								97 100
							 | 
							readdcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) e. RR )  | 
						
						
							| 102 | 
							
								101
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) e. CC )  | 
						
						
							| 103 | 
							
								80 99
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) x. ( Y ^ 2 ) ) e. RR )  | 
						
						
							| 104 | 
							
								103
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) x. ( Y ^ 2 ) ) e. CC )  | 
						
						
							| 105 | 
							
								102 104 81 87
							 | 
							divdird | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) = ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) + ( ( ( A ^ 2 ) x. ( Y ^ 2 ) ) / ( A ^ 2 ) ) ) )  | 
						
						
							| 106 | 
							
								105
							 | 
							eqcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) + ( ( ( A ^ 2 ) x. ( Y ^ 2 ) ) / ( A ^ 2 ) ) ) = ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 107 | 
							
								90 93 106
							 | 
							3eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 108 | 
							
								107
							 | 
							adantr | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 109 | 
							
								97
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + ( T x. Y ) ) e. CC )  | 
						
						
							| 110 | 
							
								100
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( B ^ 2 ) x. ( Y ^ 2 ) ) e. CC )  | 
						
						
							| 111 | 
							
								109 110 104
							 | 
							addassd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) = ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( ( B ^ 2 ) x. ( Y ^ 2 ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) ) )  | 
						
						
							| 112 | 
							
								98
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( B ^ 2 ) e. CC )  | 
						
						
							| 113 | 
							
								99
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( Y ^ 2 ) e. CC )  | 
						
						
							| 114 | 
							
								112 81 113
							 | 
							adddird | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( B ^ 2 ) + ( A ^ 2 ) ) x. ( Y ^ 2 ) ) = ( ( ( B ^ 2 ) x. ( Y ^ 2 ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) )  | 
						
						
							| 115 | 
							
								112 81
							 | 
							addcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( B ^ 2 ) + ( A ^ 2 ) ) = ( ( A ^ 2 ) + ( B ^ 2 ) ) )  | 
						
						
							| 116 | 
							
								115
							 | 
							oveq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( B ^ 2 ) + ( A ^ 2 ) ) x. ( Y ^ 2 ) ) = ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) )  | 
						
						
							| 117 | 
							
								114 116
							 | 
							eqtr3d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( B ^ 2 ) x. ( Y ^ 2 ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) = ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) )  | 
						
						
							| 118 | 
							
								117
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( ( B ^ 2 ) x. ( Y ^ 2 ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) ) = ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) ) )  | 
						
						
							| 119 | 
							
								96
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( T x. Y ) e. CC )  | 
						
						
							| 120 | 
							
								80 98
							 | 
							readdcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) + ( B ^ 2 ) ) e. RR )  | 
						
						
							| 121 | 
							
								120 99
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) e. RR )  | 
						
						
							| 122 | 
							
								121
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) e. CC )  | 
						
						
							| 123 | 
							
								38 119 122
							 | 
							addassd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) ) = ( ( C ^ 2 ) + ( ( T x. Y ) + ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) ) ) )  | 
						
						
							| 124 | 
							
								119 122
							 | 
							addcomd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( T x. Y ) + ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) ) = ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) )  | 
						
						
							| 125 | 
							
								124
							 | 
							oveq2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + ( ( T x. Y ) + ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) ) ) = ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) )  | 
						
						
							| 126 | 
							
								123 125
							 | 
							eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) ) = ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) )  | 
						
						
							| 127 | 
							
								111 118 126
							 | 
							3eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) = ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) )  | 
						
						
							| 128 | 
							
								127
							 | 
							adantr | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) = ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) )  | 
						
						
							| 129 | 
							
								128
							 | 
							oveq1d | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( ( ( ( C ^ 2 ) + ( T x. Y ) ) + ( ( B ^ 2 ) x. ( Y ^ 2 ) ) ) + ( ( A ^ 2 ) x. ( Y ^ 2 ) ) ) / ( A ^ 2 ) ) = ( ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 130 | 
							
								1
							 | 
							oveq1i | 
							 |-  ( Q x. ( Y ^ 2 ) ) = ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) )  | 
						
						
							| 131 | 
							
								3
							 | 
							oveq2i | 
							 |-  ( ( T x. Y ) + U ) = ( ( T x. Y ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) )  | 
						
						
							| 132 | 
							
								130 131
							 | 
							oveq12i | 
							 |-  ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( ( T x. Y ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 133 | 
							
								
							 | 
							rpre | 
							 |-  ( R e. RR+ -> R e. RR )  | 
						
						
							| 134 | 
							
								133
							 | 
							resqcld | 
							 |-  ( R e. RR+ -> ( R ^ 2 ) e. RR )  | 
						
						
							| 135 | 
							
								134
							 | 
							3ad2ant2 | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( R ^ 2 ) e. RR )  | 
						
						
							| 136 | 
							
								80 135
							 | 
							remulcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) x. ( R ^ 2 ) ) e. RR )  | 
						
						
							| 137 | 
							
								37 136
							 | 
							resubcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) e. RR )  | 
						
						
							| 138 | 
							
								137
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) e. CC )  | 
						
						
							| 139 | 
							
								122 119 138
							 | 
							addassd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( ( T x. Y ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) ) )  | 
						
						
							| 140 | 
							
								132 139
							 | 
							eqtr4id | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 141 | 
							
								140
							 | 
							eqeq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 <-> ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = 0 ) )  | 
						
						
							| 142 | 
							
								121 96
							 | 
							readdcld | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) e. RR )  | 
						
						
							| 143 | 
							
								142
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) e. CC )  | 
						
						
							| 144 | 
							
								
							 | 
							addeq0 | 
							 |-  ( ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) e. CC /\ ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) e. CC ) -> ( ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = 0 <-> ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 145 | 
							
								143 138 144
							 | 
							syl2anc | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) + ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = 0 <-> ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 146 | 
							
								141 145
							 | 
							bitrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 <-> ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 147 | 
							
								
							 | 
							oveq2 | 
							 |-  ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) -> ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) = ( ( C ^ 2 ) + -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 148 | 
							
								147
							 | 
							oveq1d | 
							 |-  ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) -> ( ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) / ( A ^ 2 ) ) = ( ( ( C ^ 2 ) + -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 149 | 
							
								38 138
							 | 
							negsubd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = ( ( C ^ 2 ) - ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) )  | 
						
						
							| 150 | 
							
								136
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A ^ 2 ) x. ( R ^ 2 ) ) e. CC )  | 
						
						
							| 151 | 
							
								38 150
							 | 
							nncand | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) - ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = ( ( A ^ 2 ) x. ( R ^ 2 ) ) )  | 
						
						
							| 152 | 
							
								149 151
							 | 
							eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C ^ 2 ) + -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) = ( ( A ^ 2 ) x. ( R ^ 2 ) ) )  | 
						
						
							| 153 | 
							
								152
							 | 
							oveq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) / ( A ^ 2 ) ) = ( ( ( A ^ 2 ) x. ( R ^ 2 ) ) / ( A ^ 2 ) ) )  | 
						
						
							| 154 | 
							
								135
							 | 
							recnd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( R ^ 2 ) e. CC )  | 
						
						
							| 155 | 
							
								154 81 87
							 | 
							divcan3d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( A ^ 2 ) x. ( R ^ 2 ) ) / ( A ^ 2 ) ) = ( R ^ 2 ) )  | 
						
						
							| 156 | 
							
								153 155
							 | 
							eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( C ^ 2 ) + -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) / ( A ^ 2 ) ) = ( R ^ 2 ) )  | 
						
						
							| 157 | 
							
								148 156
							 | 
							sylan9eqr | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) ) -> ( ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) / ( A ^ 2 ) ) = ( R ^ 2 ) )  | 
						
						
							| 158 | 
							
								157
							 | 
							ex | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) = -u ( ( C ^ 2 ) - ( ( A ^ 2 ) x. ( R ^ 2 ) ) ) -> ( ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) / ( A ^ 2 ) ) = ( R ^ 2 ) ) )  | 
						
						
							| 159 | 
							
								146 158
							 | 
							sylbid | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 -> ( ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) / ( A ^ 2 ) ) = ( R ^ 2 ) ) )  | 
						
						
							| 160 | 
							
								159
							 | 
							imp | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( ( C ^ 2 ) + ( ( ( ( A ^ 2 ) + ( B ^ 2 ) ) x. ( Y ^ 2 ) ) + ( T x. Y ) ) ) / ( A ^ 2 ) ) = ( R ^ 2 ) )  | 
						
						
							| 161 | 
							
								108 129 160
							 | 
							3eqtrd | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) )  | 
						
						
							| 162 | 
							
								30 31 19
							 | 
							divcan2d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( A x. ( ( C - ( B x. Y ) ) / A ) ) = ( C - ( B x. Y ) ) )  | 
						
						
							| 163 | 
							
								162
							 | 
							oveq1d | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = ( ( C - ( B x. Y ) ) + ( B x. Y ) ) )  | 
						
						
							| 164 | 
							
								33 34
							 | 
							npcand | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( C - ( B x. Y ) ) + ( B x. Y ) ) = C )  | 
						
						
							| 165 | 
							
								163 164
							 | 
							eqtrd | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = C )  | 
						
						
							| 166 | 
							
								165
							 | 
							adantr | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = C )  | 
						
						
							| 167 | 
							
								161 166
							 | 
							jca | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> ( ( ( ( ( C - ( B x. Y ) ) / A ) ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. ( ( C - ( B x. Y ) ) / A ) ) + ( B x. Y ) ) = C ) )  | 
						
						
							| 168 | 
							
								21 29 167
							 | 
							rspcedvd | 
							 |-  ( ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) /\ ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) -> E. x e. RR ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) )  | 
						
						
							| 169 | 
							
								168
							 | 
							ex | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 -> E. x e. RR ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) ) )  | 
						
						
							| 170 | 
							
								11 169
							 | 
							impbid | 
							 |-  ( ( ( ( A e. RR /\ A =/= 0 ) /\ B e. RR /\ C e. RR ) /\ R e. RR+ /\ Y e. RR ) -> ( E. x e. RR ( ( ( x ^ 2 ) + ( Y ^ 2 ) ) = ( R ^ 2 ) /\ ( ( A x. x ) + ( B x. Y ) ) = C ) <-> ( ( Q x. ( Y ^ 2 ) ) + ( ( T x. Y ) + U ) ) = 0 ) )  |