| Step | Hyp | Ref | Expression | 
						
							| 1 |  | wlkop | ⊢ ( 𝑊  ∈  ( Walks ‘ 𝐺 )  →  𝑊  =  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉 ) | 
						
							| 2 |  | wlkvv | ⊢ ( ( 1st  ‘ 𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd  ‘ 𝑊 )  →  𝑊  ∈  ( V  ×  V ) ) | 
						
							| 3 |  | 1st2ndb | ⊢ ( 𝑊  ∈  ( V  ×  V )  ↔  𝑊  =  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉 ) | 
						
							| 4 | 2 3 | sylib | ⊢ ( ( 1st  ‘ 𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd  ‘ 𝑊 )  →  𝑊  =  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉 ) | 
						
							| 5 |  | eleq1 | ⊢ ( 𝑊  =  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉  →  ( 𝑊  ∈  ( Walks ‘ 𝐺 )  ↔  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉  ∈  ( Walks ‘ 𝐺 ) ) ) | 
						
							| 6 |  | df-br | ⊢ ( ( 1st  ‘ 𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd  ‘ 𝑊 )  ↔  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉  ∈  ( Walks ‘ 𝐺 ) ) | 
						
							| 7 | 5 6 | bitr4di | ⊢ ( 𝑊  =  〈 ( 1st  ‘ 𝑊 ) ,  ( 2nd  ‘ 𝑊 ) 〉  →  ( 𝑊  ∈  ( Walks ‘ 𝐺 )  ↔  ( 1st  ‘ 𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd  ‘ 𝑊 ) ) ) | 
						
							| 8 | 1 4 7 | pm5.21nii | ⊢ ( 𝑊  ∈  ( Walks ‘ 𝐺 )  ↔  ( 1st  ‘ 𝑊 ) ( Walks ‘ 𝐺 ) ( 2nd  ‘ 𝑊 ) ) |