Answer:
Explanation:
Given: c is parallel to d and ∠4=∠5.
To prove: ∠7=∠8
Proof:
Statement Reason
1. c║d, ∠4=∠5 Given
2.∠4=∠7 If lines ||, alternate interior angles are equal.
3.∠5=∠8 Vertical angles are equal
Since, ∠4=∠5, therefore ∠7=∠8
4.∠7=∠8 Substitution