Answer:
x = 165°
Step-by-step explanation:
x° = 360 - (the measure of one interior angle of the octagon + the measure of one interior angle of the equilateral ∆)
Each interior angle of a regular octagon = 135° ([tex] \frac{(n - 2)180}{n} = 135°)
An equilateral ∆ has equal angles, each measuring 60°.
Therefore:
x° = 360° - (135° + 60°)
x = 360 - 195
x = 165°
