First, find the sum of the interior angles using the formula: (𝒏 – 2) × 180 = (8 – 2) × 180 = 6 × 180 = 1080. Then divide this by the number of sides, eight: 1080 divided by 8 = 135.

Learn more about how angles in an 𝒏-sided polygon add to 180° × (𝒏 – 2) with this BBC Bitesize Maths article. For students between the ages of 11 and 14.