Question 48 Answer and Explanation _ACT October 2014 Asia Form 70B Math Section

48. Max's design for a rectangular stained glass window with 7 triangles is shown below. The 2 white triangles are congruent (△ABC $\cong$ △DEC) and will be a different color than the other 5 triangles. The design includes the measures of ∠CAB，∠ACB，and ∠DCE. Max can find the measure of ∠BCE with which of the following additional pieces of information?

F. The measure of ∠ABC

G. The measure of ∠ABE

H. The measure of ∠CDE

J. The length of BC

K. The length of DE

Answer and Explanation

Your Answer is

Correct Answer is G

Explanation

Knowing the angle ABE is equivalent to knowing the angle CBE and the angle CEB, and then the angle BCE can be deduced according to the principle of the interior angle of a triangle and 180 degrees.