| Step | Hyp | Ref | Expression | 
						
							| 1 |  | simpr |  | 
						
							| 2 | 1 | nn0cnd |  | 
						
							| 3 |  | rernegcl |  | 
						
							| 4 | 3 | ad2antrr |  | 
						
							| 5 | 4 | recnd |  | 
						
							| 6 |  | simpll |  | 
						
							| 7 | 6 | recnd |  | 
						
							| 8 | 2 5 7 | addassd |  | 
						
							| 9 |  | renegid2 |  | 
						
							| 10 | 9 | ad2antrr |  | 
						
							| 11 | 10 | oveq2d |  | 
						
							| 12 |  | nn0re |  | 
						
							| 13 |  | readdrid |  | 
						
							| 14 | 12 13 | syl |  | 
						
							| 15 | 14 | adantl |  | 
						
							| 16 | 8 11 15 | 3eqtrrd |  | 
						
							| 17 | 9 | oveq1d |  | 
						
							| 18 | 17 | adantr |  | 
						
							| 19 |  | readdlid |  | 
						
							| 20 | 12 19 | syl |  | 
						
							| 21 | 18 20 | sylan9eq |  | 
						
							| 22 |  | nnnn0 |  | 
						
							| 23 |  | nn0addcom |  | 
						
							| 24 | 22 23 | sylan |  | 
						
							| 25 | 24 | adantll |  | 
						
							| 26 | 25 | oveq1d |  | 
						
							| 27 | 16 21 26 | 3eqtr4d |  | 
						
							| 28 | 5 7 2 | addassd |  | 
						
							| 29 | 5 2 7 | addassd |  | 
						
							| 30 | 27 28 29 | 3eqtr3d |  | 
						
							| 31 | 7 2 | addcld |  | 
						
							| 32 | 2 7 | addcld |  | 
						
							| 33 | 5 31 32 | sn-addcand |  | 
						
							| 34 | 30 33 | mpbid |  |