Understanding Quadrilaterals

Quadrilaterals are four-sided closed polygons that form the foundation for understanding shapes, angles, and symmetry in geometry. This topic covers their properties, types, angle sums, and the relationships that disting…

• A quadrilateral is a closed plane figure with four sides, four vertices, and four angles.
• The sum of interior angles of any quadrilateral is always $360^\circ$.
• A diagonal divides a quadrilateral into two triangles, each summing to $180^\circ$.

Full explanation, worked examples & memory tricks in the app