| Step | Hyp | Ref | Expression | 
						
							| 1 |  | decma.a |  | 
						
							| 2 |  | decma.b |  | 
						
							| 3 |  | decma.c |  | 
						
							| 4 |  | decma.d |  | 
						
							| 5 |  | decma.m | Could not format  M = ; A B : No typesetting found for |- M = ; A B with typecode |- | 
						
							| 6 |  | decma.n | Could not format  N = ; C D : No typesetting found for |- N = ; C D with typecode |- | 
						
							| 7 |  | decma2c.p |  | 
						
							| 8 |  | decma2c.f |  | 
						
							| 9 |  | decma2c.g |  | 
						
							| 10 |  | decma2c.e |  | 
						
							| 11 |  | decma2c.2 | Could not format  ( ( P x. B ) + D ) = ; G F : No typesetting found for |- ( ( P x. B ) + D ) = ; G F with typecode |- | 
						
							| 12 |  | 10nn0 |  | 
						
							| 13 |  | dfdec10 | Could not format  ; A B = ( ( ; 1 0 x. A ) + B ) : No typesetting found for |- ; A B = ( ( ; 1 0 x. A ) + B ) with typecode |- | 
						
							| 14 | 5 13 | eqtri |  | 
						
							| 15 |  | dfdec10 | Could not format  ; C D = ( ( ; 1 0 x. C ) + D ) : No typesetting found for |- ; C D = ( ( ; 1 0 x. C ) + D ) with typecode |- | 
						
							| 16 | 6 15 | eqtri |  | 
						
							| 17 |  | dfdec10 | Could not format  ; G F = ( ( ; 1 0 x. G ) + F ) : No typesetting found for |- ; G F = ( ( ; 1 0 x. G ) + F ) with typecode |- | 
						
							| 18 | 11 17 | eqtri |  | 
						
							| 19 | 12 1 2 3 4 14 16 7 8 9 10 18 | numma2c |  | 
						
							| 20 |  | dfdec10 | Could not format  ; E F = ( ( ; 1 0 x. E ) + F ) : No typesetting found for |- ; E F = ( ( ; 1 0 x. E ) + F ) with typecode |- | 
						
							| 21 | 19 20 | eqtr4i | Could not format  ( ( P x. M ) + N ) = ; E F : No typesetting found for |- ( ( P x. M ) + N ) = ; E F with typecode |- |