| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lplnnleat.l |  |-  .<_ = ( le ` K ) | 
						
							| 2 |  | lplnnleat.a |  |-  A = ( Atoms ` K ) | 
						
							| 3 |  | lplnnleat.p |  |-  P = ( LPlanes ` K ) | 
						
							| 4 |  | simp1 |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> K e. HL ) | 
						
							| 5 |  | simp2 |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> X e. P ) | 
						
							| 6 |  | simp3 |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> Q e. A ) | 
						
							| 7 |  | eqid |  |-  ( join ` K ) = ( join ` K ) | 
						
							| 8 | 1 7 2 3 | lplnnle2at |  |-  ( ( K e. HL /\ ( X e. P /\ Q e. A /\ Q e. A ) ) -> -. X .<_ ( Q ( join ` K ) Q ) ) | 
						
							| 9 | 4 5 6 6 8 | syl13anc |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> -. X .<_ ( Q ( join ` K ) Q ) ) | 
						
							| 10 | 7 2 | hlatjidm |  |-  ( ( K e. HL /\ Q e. A ) -> ( Q ( join ` K ) Q ) = Q ) | 
						
							| 11 | 10 | 3adant2 |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> ( Q ( join ` K ) Q ) = Q ) | 
						
							| 12 | 11 | breq2d |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> ( X .<_ ( Q ( join ` K ) Q ) <-> X .<_ Q ) ) | 
						
							| 13 | 9 12 | mtbid |  |-  ( ( K e. HL /\ X e. P /\ Q e. A ) -> -. X .<_ Q ) |