Question

Solving for Unknown Interior Angles of a Triangle
Megan constructed triangle ABC. In Megan’s triangle, m∠A is represented by x°, m∠B is 4 times greater than m∠A, and m∠C is 30° less than 5 times m∠A.

m∠A = x°

m∠B = (4x)°

m∠C = (5x − 30)°

What is the measure of each angle in Megan’s triangle?

m∠A =
°
m∠B =
°
m∠C =
°

Answer 1

Set up the angle sum: x + 4x + (5x − 30) = 180
10x − 30 = 180
10x = 210
x = 21

m∠A = 21°
m∠B = 4x = 84°
m∠C = 5x − 30 = 75°