| Step | Hyp | Ref | Expression | 
						
							| 1 |  | s2eqd.1 |  |-  ( ph -> A = N ) | 
						
							| 2 |  | s2eqd.2 |  |-  ( ph -> B = O ) | 
						
							| 3 |  | s3eqd.3 |  |-  ( ph -> C = P ) | 
						
							| 4 |  | s4eqd.4 |  |-  ( ph -> D = Q ) | 
						
							| 5 |  | s5eqd.5 |  |-  ( ph -> E = R ) | 
						
							| 6 | 1 2 3 4 | s4eqd |  |-  ( ph -> <" A B C D "> = <" N O P Q "> ) | 
						
							| 7 | 5 | s1eqd |  |-  ( ph -> <" E "> = <" R "> ) | 
						
							| 8 | 6 7 | oveq12d |  |-  ( ph -> ( <" A B C D "> ++ <" E "> ) = ( <" N O P Q "> ++ <" R "> ) ) | 
						
							| 9 |  | df-s5 |  |-  <" A B C D E "> = ( <" A B C D "> ++ <" E "> ) | 
						
							| 10 |  | df-s5 |  |-  <" N O P Q R "> = ( <" N O P Q "> ++ <" R "> ) | 
						
							| 11 | 8 9 10 | 3eqtr4g |  |-  ( ph -> <" A B C D E "> = <" N O P Q R "> ) |