| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mulgsubdi.b |  | 
						
							| 2 |  | mulgsubdi.t |  | 
						
							| 3 |  | mulgsubdi.d |  | 
						
							| 4 |  | simpl |  | 
						
							| 5 |  | simpr1 |  | 
						
							| 6 |  | simpr2 |  | 
						
							| 7 |  | ablgrp |  | 
						
							| 8 | 7 | adantr |  | 
						
							| 9 |  | simpr3 |  | 
						
							| 10 |  | eqid |  | 
						
							| 11 | 1 10 | grpinvcl |  | 
						
							| 12 | 8 9 11 | syl2anc |  | 
						
							| 13 |  | eqid |  | 
						
							| 14 | 1 2 13 | mulgdi |  | 
						
							| 15 | 4 5 6 12 14 | syl13anc |  | 
						
							| 16 | 1 2 10 | mulginvcom |  | 
						
							| 17 | 8 5 9 16 | syl3anc |  | 
						
							| 18 | 17 | oveq2d |  | 
						
							| 19 | 15 18 | eqtrd |  | 
						
							| 20 | 1 13 10 3 | grpsubval |  | 
						
							| 21 | 6 9 20 | syl2anc |  | 
						
							| 22 | 21 | oveq2d |  | 
						
							| 23 | 1 2 | mulgcl |  | 
						
							| 24 | 8 5 6 23 | syl3anc |  | 
						
							| 25 | 1 2 | mulgcl |  | 
						
							| 26 | 8 5 9 25 | syl3anc |  | 
						
							| 27 | 1 13 10 3 | grpsubval |  | 
						
							| 28 | 24 26 27 | syl2anc |  | 
						
							| 29 | 19 22 28 | 3eqtr4d |  |