| Step | Hyp | Ref | Expression | 
						
							| 1 |  | renegid |  | 
						
							| 2 | 1 | adantr |  | 
						
							| 3 | 2 | oveq1d |  | 
						
							| 4 |  | simpl |  | 
						
							| 5 | 4 | recnd |  | 
						
							| 6 |  | rernegcl |  | 
						
							| 7 | 6 | adantr |  | 
						
							| 8 | 7 | recnd |  | 
						
							| 9 |  | elre0re |  | 
						
							| 10 | 9 9 | readdcld |  | 
						
							| 11 |  | rernegcl |  | 
						
							| 12 | 10 11 | syl |  | 
						
							| 13 |  | id |  | 
						
							| 14 | 12 13 | readdcld |  | 
						
							| 15 | 14 | adantl |  | 
						
							| 16 | 15 | recnd |  | 
						
							| 17 | 5 8 16 | addassd |  | 
						
							| 18 |  | resubeulem1 |  | 
						
							| 19 | 18 | oveq1d |  | 
						
							| 20 | 9 | recnd |  | 
						
							| 21 | 12 | recnd |  | 
						
							| 22 |  | recn |  | 
						
							| 23 | 20 21 22 | addassd |  | 
						
							| 24 |  | reneg0addlid |  | 
						
							| 25 | 19 23 24 | 3eqtr3d |  | 
						
							| 26 | 25 | adantl |  | 
						
							| 27 | 3 17 26 | 3eqtr3d |  |