Question

In the triangle below, what is the measure (in degrees) of angle X?
66°
55°
X

Answer 1

59°

Explanation:

A triangle's angles add up to 180°.

So to find the last angle of the shape, you need to add the given angles and then subtract the answer from 180° looking like this:

66° + 55° = 121°

180° - 121° = 59°

Answer 2

59

Explanation:

Angle degrees in a triangle add up to 180

66+55+x=180

121+x=180

x=59