| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 0red |  | 
						
							| 2 |  | 1re |  | 
						
							| 3 |  | rersubcl |  | 
						
							| 4 | 2 2 3 | mp2an |  | 
						
							| 5 | 4 | a1i |  | 
						
							| 6 |  | ax-icn |  | 
						
							| 7 | 6 6 | mulcli |  | 
						
							| 8 |  | ax-1cn |  | 
						
							| 9 | 4 | recni |  | 
						
							| 10 | 7 8 9 | addassi |  | 
						
							| 11 |  | repncan3 |  | 
						
							| 12 | 2 2 11 | mp2an |  | 
						
							| 13 | 12 | oveq2i |  | 
						
							| 14 | 10 13 | eqtri |  | 
						
							| 15 |  | ax-i2m1 |  | 
						
							| 16 | 15 | oveq1i |  | 
						
							| 17 | 14 16 15 | 3eqtr3i |  | 
						
							| 18 | 17 | a1i |  | 
						
							| 19 | 1 5 18 | reladdrsub |  | 
						
							| 20 | 19 | mptru |  |