Answer:
x = 79
Explanation:
All triangles have a sum of 180°. Knowing this, we can solve for the unknown angle.
56 + 23 + ? = 180
79 + ? = 180
? = 101
The variable x is known as an exterior angle. That and the angle we just solved for are supplementary meaning they add up to 180°.
101 + x = 180
x = 79