9. Which of the following is a counterexample of this statement? If an angle is acute, then it measures 80°.
A. a 100° angle
B. a 90° angle
C. an 80° angle
D. a 70° angle

Which of the following correctly justifies statement four of the two column proof? a. corresponding angles theorem b. transitive property of equality c. vertical angle theorem d. substitution property of equality

Two angles are complementary. the large angle is 36 more than the smaller angle. what is the measure of the large angle?

Select the correct answer. what is the exact value of sin (157.5°)? a. 'sqrt(2 - sqrt(2))/2 b. *"-"'sqrt(2 + sqrt(2))/29 c.'sqrt(2 + sqrt(2))/4" d. "-"sqrt(2 + sqrt(2))/4)