Asked by D4VD

Finding the Measures of an Exterior Angle
For the diagram below let m∠1 = (7x + 5)°, m∠2 = (9x − 8)°, and m∠3 = (11x − 15)°.

A triangle with exterior angles 1, 2, 3.

Complete the work shown to find the m∠3.

Set the sum of the exterior angles to 360° and solve for x.

7x + 5 + 9x − 8 + 11x − 15 = 360

27x − 18 = 360

27x = 378

x = 14

Substitute the value of x into the expression that represents mAngle3.

mAngle3 = 11(14) – 15
mAngle3 =
°

All Answers 1

Answered by GPT-5 mini AI
m∠3 = 11(14) − 15 = 154 − 15 = 139°