Question 42 Answer and Explanation _ACT June 2013 Form 71C Math Section

42. In the figure below, X and Z are on line m, and Y is on line $l$ . The exterior angle to △XYZ at Z measures 160°. One of the following statements gives sufficient additional information to find the measure of ∠b. Which one?

F. Line l is parallel to line m.

G. The measure of ∠d is 130°.

H. The measure of ∠c is equal to the measure of ∠f.

J. The measure of ∠a is greater than the measure of ∠c.

K. The sum of the measures of ∠b, ∠e, and ∠f is 180°.

Answer and Explanation

Your Answer is

Correct Answer is G

Explanation

This question requires substituting the conditions of the options one by one to determine whether ∠b can be solved. The information in the G option can determine ∠e, and we can solve it by ∠b=180-∠e-∠f.