An octagon has 8 sides.
Sum of interior angles = 180° x (n-2) = 180° x (8-2) = 180° x 6 = 1,080°
1,080° ÷ 8 sides = 135° interior angle.
Angle 2 = 135° / 2 = 67.50°
Angle 1 = 180° - 135° = 45°
If these were the choices given:
a. mangle1 = 45°, mangle2 = 135°
b. mangle1 = 45°, mangle2 = 67.5° ⇔ THIS IS THE CORRECT ANSWER.
c. mangle1 = mangle2 = 60°
d. mangle1 = 22.5°, mangle2 = 78.75°