Given: Angle A and Angle B are complementary angles. Angle B and Angle C are complementary angles.
Prove: The measure of Angle A = the measure of Angle C.
Statements Reasons
1. Angle A and Angle B are complementary angles. given
2. Angle B and Angle C are complementary angles. given
3. The measure of Angle A + the measure of Angle B = 90 degrees. Definition of Complementary Angles
4. The measure of Angle C + the measure of Angle B = 90 degrees. Definition of Complementary Angles
5. The measure of Angle A + the measure of Angle B = the measure of Angle C + the measure of Angle B. Transitive Property of Equality[^t43]
6. The measure of Angle A = the measure of Angle C. Subtraction Property of Equality [^t44]