Question

Work out the interior angle of the octagon.
Please show the working out.

Answer 1

135°

Explanation:

formula = (n-2) * 180, whereby 'n' is the number of sides.

therefore, (8-2) * 180 = 1080°

1080° ÷ number of sides

= 1080° ÷ 8

= 135°

Answer 2

∠a = 135°

Explanation:

There is a formula for finding the sum of the interior angles of any polygon.

N = number of sides

sum of interior angles = (180° x N) - 360°

so:

(180° x 8) - 360° = 1080°

1080°/8 angles = 135° each angle