Key learning points

1. Quadrilaterals can be described and identified using their properties.
2. Triangles can be classified according to their properties.
3. Polygons can be regular or irregular.

Keywords

• Regular - A regular polygon has sides that are all equal and interior (inside) angles that are all equal.

• Irregular - An irregular polygon has sides that are not equal or interior (inside) angles that are not equal.

• Quadrilateral - Quadrilaterals are polygons that have 4 sides.

• Polygon - A polygon is a flat (2D), closed figure made up of straight line segments.

• Parallel - Two lines are parallel if they are straight lines that are always the same (non-zero) distance apart.

Common misconception