Mathematics · Class 8
Understanding Quadrilaterals
Types of quadrilaterals, parallelogram properties, and angle sums.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Quadrilaterals are four-sided polygons. Study types — parallelogram, rectangle, rhombus, square, kite, trapezium — and their angle and side properties.
Angle Sum
Quadrilateral
Sum of four interior angles = 360°
Parallelogram Properties
- Opposite sides parallel and equal
- Opposite angles equal
- Diagonals bisect each other
- Adjacent angles supplementary
Special Parallelograms
- Rectangle: all angles 90°
- Rhombus: all sides equal
- Square: rectangle + rhombus properties
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Example 1: Find Angle
Three angles of quadrilateral are 80°, 95°, 110°. Find fourth.
- 1Sum = 360°
- 2Fourth = 360 − 285
Answer
75°
Example 2: Parallelogram
In parallelogram ABCD, ∠A = 70°. Find ∠B and ∠C.
- 1Adjacent supplementary: ∠B = 110°
- 2Opposite equal: ∠C = 70°
Answer
∠B = 110°, ∠C = 70°
Key Points to Remember
- ✓ Kite: two pairs of adjacent equal sides
- ✓ Trapezium: one pair of parallel sides
- ✓ Square has all symmetry properties
Exam Tips
- • Use properties, don't assume unless stated
- • Mark parallel sides with arrows
Practice MCQs — Understanding Quadrilaterals
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
Sum of angles in quadrilateral: