# Class 8 Maths Chapter 3 Understanding Quadrilaterals MCQs

Class 8 Maths Chapter 3 Understanding Quadrilaterals MCQs (Questions and Answers) are provided here, online. These objective questions are designed for students, as per the CBSE syllabus (2021-2022) and NCERT guidelines. Solving the chapter-wise questions will help students understand each concept and help to score good marks in exams. Also, learn important questions for class 8 Maths here at BYJU’S.

Practice more and test your skills on Class 8 Maths Chapter 3 Understanding Quadrilaterals MCQs with the given PDF here.

## MCQs on Class 8 Understanding Quadrilaterals

Multiple Choice Questions (MCQs) are available for Class 8 Understanding Quadrilaterals chapter. Each problem consists of four multiple options, out of which one is the correct answer. Students have to solve the problem and select the correct answer.

**1. Which of the following is not a quadrilateral?**

A. Square

B. Rectangle

C. Triangle

D. Parallelogram

Answer: **C**

Explanation: A quadrilateral is a four-sided polygon but triangle is a three-sided polygon.

**2. Which of the following quadrilaterals has two pairs of adjacent sides equal and its diagonals intersect at 90 degrees?**

A. Square

B. Kite

C. Rhombus

D. Rectangle

Answer: **B**

**3. Which one of the following is a regular quadrilateral?**

A. Square

B. Trapezium

C. Kite

D. Rectangle

Answer: **A**

Explanation: A square has all its sides equal and angles equal to 90 degrees.

**4. If AB and CD are two parallel sides of a parallelogram, then:**

A. AB>CD

B. AB<CD

C. AB=CD

D. None of the above

Answer: **C**

**5. The perimeter of a parallelogram whose parallel sides have lengths equal to 12 cm and 7 cm is:**

A. 21 cm

B. 42 cm

C. 19 cm

D. 38 cm

Answer: **D**

Explanation: Perimeter of parallelogram = 2 (Sum of Parallel sides)

P = 2 (12 + 7)

P = 2 (19)

P = 38 cm

**6. If ∠A and ∠C are two opposite angles of a parallelogram, then:**

A. ∠A > ∠C

B. ∠A = ∠C

C. ∠A < ∠C

D. None of the above

Answer: **B**

Explanation: Opposite angles of a parallelogram are always equal.

**7. If ∠A and ∠B are two adjacent angles of a parallelogram. If ∠A = 70**°**, then ∠B = ?**

A. 70°

B. 90°

C. 110°

D. 180°

Answer: **C**

Explanation: The adjacent angles of parallelogram are supplementary.

∠A + ∠B = 180°

70° + ∠B = 180°

∠B = 180 – 70° = 110°

**8. ABCD is a rectangle and AC & BD are its diagonals. If AC = 10 cm, then BD is:**

A. 10 cm

B. 5 cm

C. 15 cm

D. 20 cm

Answer: **A**

Explanation: The diagonals of a rectangle are always equal.

**9. Each of the angles of a square is:**

A. Acute angle

B. Right angle

C. Obtuse angle

D. 180 degrees

Answer: **B**

Explanation: All the angles of square is at right angle.

**10. The quadrilateral whose diagonals are perpendicular to each other is:**

A. Parallelogram

B. Rectangle

C. Trapezium

D. Rhombus

Answer: **D**

**11. Which of the following is not a regular polygon?**

A. Square

B. Equilateral triangle

C. Rectangle

D. Regular hexagon

Answer: C. Rectangle

Explanation: A regular polygon is both equiangular and equilateral. But all four sides of a rectangle are not equal, thus it is not a regular polygon.

**12. If the two angles of a triangle are 80° and 50°, respectively. Find the measure of the third angle.**

A. 50°

B. 60°

C. 70°

D. 80°

Answer: A. 50°

Explanation: By the angle sum property of triangle, we know that;

Sum of all the angles of a triangle = 180°

Let the unknown angle be x

80° + 50° + x = 180°

x = 180° – 130°

x = 50°

**13. In a parallelogram ABCD, angle A and angle B are in the ratio 1:2. Find the angle A.**

A. 30°

B. 45°

C. 60°

D. 90°

Answer: C.60°

Explanation: As we know, the sum of adjacent angles of a parallelogram is equal to 180° and opposite angles are equal to each other.

Thus, in parallelogram ABCD angle A and angle B are adjacent to each other

Let angle A = x and angle B = 2x.

So, x + 2x = 180°

3x = 180°

x = 60°

**14. The angles of a quadrilateral are in ratio 1:2:3:4. Which angle has the largest measure?**

A. 120°

B. 144°

C. 98°

D. 36°

Answer: B.144°

Explanation: Suppose, ABCD is a quadrilateral.

Let angle A is x

Then,

x + 2x + 3x + 4x = 360° [Angle sum property of quadrilateral]
10x = 360°

x = 36°

Hence, the greatest angle is 4x = 4 x 36 = 144°

**15. The length and breadth of a rectangle is 4 cm and 2 cm respectively. Find the perimeter of the rectangle.**

A. 12 cm

B. 6 cm

C. 8 cm

D. 16 cm

Answer: A. 12 cm

Explanation: Given, length of rectangle is 4 cm

Breadth of rectangle = 2cm

By the formula of perimeter of rectangle, we know that;

Perimeter = 2 (Length + Breadth)

P = 2(4+2)

P = 2 x 6

P = 12 cm

**16. The diagonals of a rectangle are 2x + 1 and 3x – 1, respectively. Find the value of x.**

A. 1

B. 2

C. 3

D. 4

Answer: B.2

Explanation: The diagonals of a rectangle are equal in length.

2x + 1 = 3x -1

1 + 1 = 3x – 2x

2 = x

Thus, the value of x is 2.

**17. The diagonals of a kite:**

A. Bisects each other

B. Are perpendicular to each other

C. Does not bisect each other

D. None of the above

Answer: B. Are perpendicular to each other

Explanation: The diagonals of a kite are perpendicular to each other. They intersect at 90 degrees but does not bisect.

**18. A rhombus has a side length equal to 5 cm. Find its perimeter.**

A. 25

B. 10

C. 20

D. 30

Answer: C. 20

Explanation: A rhombus is a parallelogram that has all its four sides equal. Thus, the perimeter of rhombus,

P = 4 x side-length

P = 4 x 5

P = 20 cm

**19. ABCD is a parallelogram. If angle A is equal to 45°, then find the measure of its adjacent angle.**

A. 135°

B. 120°

C. 115°

D. 180°

Answer: A.135°

Explanation: The adjacent angles of a parallelogram sums up to 180°.

Thus,

45° + x = 180°

x = 180° – 45°

x = 135°

**20. The kite has exactly two distinct consecutive pairs of sides of equal length.**

A. True

B. False

Answer: A. True

Explanation: A kite is a quadrilateral that has exactly two distinct consecutive pairs of sides of equal length.