Question

Select the reason that best
supports Statement 5 in the
given proof.

Answer 1

B) Subtraction Property of Equality

Explanation:

To get m∠B=77º, the problem subtracted 103º from both sides of 103º+m∠B=180º.

The Subtraction Property of Equality states that if x=y, then x-a=y-a.

In this case x=103º+m∠B, y=180º, and a=103º.