Question

In ARST, mZR = (5x – 11)", mZS = (3x – 3)°, and m_T = (3x + 18)º.
Find mZR.

Answer 1

m∠R = 69

Explanation:

m∠R + m∠S + m∠T = 180 {Angle sum property of triangle}

5x - 11 + 3x - 3 + 3x + 18 = 180

5x + 3x + 3x - 11 - 3 + 18 = 180 {Combine like terms}

11x +4 = 180

11x = 180 - 4

11x = 176

x = 176/11

x = 16

m∠R = 5x - 11

= 5*16 - 11

= 80 - 11

m∠R = 69