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Home > CC2 > Chapter 9 > Lesson 9.1.1 > Problem 9-21

9-21.

Review the definitions of complementary, supplementary, and vertical angles. Use the information to answer the following questions.  

  1. Two angles are complementary. If one measures , what is the measure of the other angle?

    Two angles whose measurements add up to  are called complementary.

  2. Two angles are supplementary. If one measures , what is the measure of the other angle?

    Two angles whose measurements add up to  are called supplementary.

  3. Two angles are vertical. If one measures , what is the measure of the other angle?

    Vertical angles have equal measures.