Grade 3 · Math · Lesson 25

Identify Polygons and Angles

A polygon is a flat, closed shape made of straight sides. Polygons are named by how many sides they have. Triangles have 3 sides. Quadrilaterals have 4 sides. Pentagons have 5, hexagons have 6, and octagons have 8 sides.

What this lesson teaches

1Classify polygons as triangles, quadrilaterals, or other polygons
2Identify right, acute, and obtuse angles

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