Question

A side of the triangle below has been extended to form an exterior angle of 165º. Find

the value of x.

Answer 1

x = 120°

Explanation:

the 165 degree obtuse angle forms a straight line with the upper left angle inside the triangle, therefore this angle measures 15 degrees

we know two of the three angle measures so we add all three together to find the unknown angle

x + 15 + 45 = 180

x + 60 = 180

x = 120°