Given data:
The given figure.
The expression for the vertical opposite angle is,
∠1=∠4
∠2=∠3
∠6=∠7
∠5=∠8
The expression for the alternate angle is,
∠4=∠5
∠3=∠6
The expression for adjacent angle is,
∠1=∠5
Thus, the ∠2 and ∠3, ∠4 and ∠5, and ∠1 and ∠5 are congruent angles.