Question

a student uses the vertical angles theorem and the definition of complementary angles to conclude m∠ptr = 50 in the figure. what mistake did the student make? choose the correct answer below. a. the student used the definition of complementary angles instead of the definition of supplementary angles. b. the student used the definition of complementary angles instead of the definition of right angles. c. the student used the definition of complementary angles instead of the definition of vertical angles. d. the student used the definition of vertical angles instead of the definition of right angles.

Explanation:

Vertical angles are equal. Complementary angles add up to 90 degrees and supplementary angles add up to 180 degrees. In this case, the angles are vertical, and if the student used the concept of complementary angles instead of vertical - angle equality to solve for the angle measure, it's an error. The student should have used the fact that vertical angles are equal, not the definition of complementary angles.

Answer:

A. The student used the definition of complementary angles instead of the definition of supplementary angles.