If two angles of a triangle are 45° and 75°, what is the third angle?

Q: If two angles of a triangle are 45° and 75°, what is the third angle?

The correct answer is C. The angle sum property of a triangle states that the sum of all three interior angles always equals 180°. So: Third angle = 180° - 45° - 75° = 60°. This is one of the most fundamental properties in geometry. This triangle has angles 45°, 75°, and 60° — since all angles are different, it's a scalene triangle.

Question

Accepted Answer

The angle sum property of a triangle states that the sum of all three interior angles always equals 180°. So: Third angle = 180° - 45° - 75° = 60°. This is one of the most fundamental properties in geometry. This triangle has angles 45°, 75°, and 60° — since all angles are different, it's a scalene triangle.