Angles in Polygons

MathematicsAQAEdexcelGCSEUnit: Geometry & Measures
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The basics

The Triangle Trick

The Triangle Trick

Here's a secret: EVERY polygon can be split into triangles by drawing lines from one vertex. A quadrilateral splits into 2 triangles, a pentagon into 3, a hexagon into 4... Since each triangle has 180°, you can calculate the interior angles of ANY polygon!

Visual: Polygon Interior Angles

Diagram showing how polygons split into triangles to calculate interior angles - triangle has 1 triangle (180°), square has 2 triangles (360°), pentagon has 3 triangles (540°), hexagon has 4 triangles (720°). Formula: (n-2) × 180°

Pattern: triangles = n − 2, each triangle = 180°

Now try it yourself

Quiz · Question 1 of 12

What is the sum of the interior angles of a hexagon?

Tap an answer to check it

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