Class 8 · Chapter 3
Understanding Quadrilaterals
Types of quadrilaterals; angle sum; parallelogram, rhombus, rectangle, square, kite.
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Detailed theory
Trapezium: one pair of parallel sides. Parallelogram: both pairs parallel. Rhombus: all sides equal. Rectangle: all angles right. Square: rectangle + rhombus.
Key concepts & formulas
01
Sum of interior angles of a quadrilateral .
02
In a parallelogram, opposite sides and opposite angles are equal.
03
Diagonals of a rhombus bisect each other at right angles.
04
Sum of exterior angles of any polygon .
05
In a regular -gon, each interior angle .