Theorem: An angle congruent to a right angle is right. (a.) Rewrite this theorem as an if-then statement.

If a angle is congruent to a right angle, then it is right.

(b.) Fill in the blanks below to prove this theorem.

Given: ∠ A is right
∠B ≅ ∠A
Prove: ∠ B is right
Statement Reason
1. ∠ A is right;

∠B ≅ ∠A

1.
given
2. m ∠ B = m ∠ A 2.
3. m ∠ A = 90º 3.
Transitive property of equality
4. m ∠ B = 90º 4. Transitive Property of Equality
5.
B is right
5.