GCSE Maths Practice: angles

Question 1 of 10

This question is about exterior angles of regular polygons.

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\( \begin{array}{l}\text{Find the size of the exterior angle of a regular triangle.}\end{array} \)

Choose one option:

Divide 360° by the number of sides to find each exterior angle.

An exterior angle of a polygon is formed when one side of the polygon is extended. For a regular polygon, all exterior angles are equal. The sum of all exterior angles of any polygon is always 360°. For a regular triangle, divide 360° by the number of sides (3) to find each exterior angle: 360 ÷ 3 = 120°. Understanding exterior angles is important because it helps in solving problems involving polygons, rotations, and geometric constructions. Recognizing the exterior angle allows students to relate it to interior angles since interior and exterior angles are supplementary. Practicing these calculations prepares students for GCSE geometry questions involving polygons, complex shapes, and angle rules. Always remember: sum of exterior angles = 360°, individual angle = 360 ÷ n.