Solve the problem.
-In triangle ABC, angle A is three times as large as angle C. The measure of angle B is 15° less than that of angle C. Find the measure of the angles.
A)117°, 24° and 39°
B)78°, 24° and 78°
C)117°, 24° and 78°
D)78°, 24° and 39°

Question

Quizplus · Accepted Answer

Angle A is three times as large as angle C, so let angle C = x. Then angle A = 3x. Angle B is 15° less than that of angle C, so angle B = x - 15°. The sum of the angles in a triangle is 180°, so x + 3x + (x - 15°) = 180°. Solving for x, we get x = 24°. Therefore, angle C = 24°, angle A = 3x = 72°, and angle B = x - 15° = 9°.

Solve the Problem. -In Triangle ABC, Angle a Is Three Times as Large