Chapter-4 Quadrilaterals — Online MCQ Test
MATHS · Grade 8 · CBSE(NCERT)
Practice Chapter-4 Quadrilaterals with a free chapter-wise online MCQ test.
This chapter covers: polygons - diagonals - convex polygon - concave polygon - regular polygon - angle sum property - parallelogram - rhombus - rectangle - square - kite.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter-4 Quadrilaterals — Important Questions & Answers
A quadrilateral is a polygon with how many sides?
- A. 3 sides
- B. 4 sides
- C. 5 sides
- D. 6 sides
Answer: B. 4 sides
By definition, a quadrilateral is a polygon with exactly 4 sides and 4 vertices.
By definition, a quadrilateral is a polygon with exactly 4 sides and 4 vertices.
What is the sum of all interior angles of a quadrilateral?
- A. 180°
- B. 270°
- C. 360°
- D. 540°
Answer: C. 360°
The angle sum property of a quadrilateral states that the sum of all interior angles is always 360°.
The angle sum property of a quadrilateral states that the sum of all interior angles is always 360°.
A convex polygon is one where:
- A. All interior angles are greater than 180°
- B. All interior angles are less than 180°
- C. At least one interior angle is greater than 180°
- D. Diagonals lie outside the polygon
Answer: B. All interior angles are less than 180°
In a convex polygon, all interior angles are less than 180°, and all diagonals lie inside the polygon.
In a convex polygon, all interior angles are less than 180°, and all diagonals lie inside the polygon.
How many diagonals does a quadrilateral have?
- A. 1 diagonal
- B. 2 diagonals
- C. 3 diagonals
- D. 4 diagonals
Answer: B. 2 diagonals
A quadrilateral has exactly 2 diagonals, which connect opposite vertices.
A quadrilateral has exactly 2 diagonals, which connect opposite vertices.
If three angles of a quadrilateral are 85°, 95°, and 100°, what is the fourth angle?
- A. 70°
- B. 80°
- C. 85°
- D. 90°
Answer: B. 80°
Using the angle sum property: Fourth angle = 360° - (85° + 95° + 100°) = 360° - 280° = 80°.
Using the angle sum property: Fourth angle = 360° - (85° + 95° + 100°) = 360° - 280° = 80°.
In a parallelogram ABCD, if angle A = 65°, what is angle B?
- A. 65°
- B. 115°
- C. 125°
- D. 155°
Answer: B. 115°
In a parallelogram, consecutive angles are supplementary (sum to 180°). Therefore, angle B = 180° - 65° = 115°.
In a parallelogram, consecutive angles are supplementary (sum to 180°). Therefore, angle B = 180° - 65° = 115°.
In quadrilateral ABCD, if the diagonals AC and BD bisect each other, which type of quadrilateral must it be?
- A. A kite
- B. A trapezium
- C. A parallelogram
- D. A rectangle
Answer: C. A parallelogram
The key property that diagonals bisect each other is characteristic of a parallelogram; other quadrilaterals may not have this property.
The key property that diagonals bisect each other is characteristic of a parallelogram; other quadrilaterals may not have this property.
A quadrilateral has vertices A, B, C, D where AB || DC and AB = DC. Which of the following must be true?
- A. ABCD is a rectangle
- B. ABCD is a rhombus
- C. ABCD is a parallelogram
- D. ABCD is a kite
Answer: C. ABCD is a parallelogram
If one pair of opposite sides is both parallel and equal, the quadrilateral is a parallelogram. The other properties vary.
If one pair of opposite sides is both parallel and equal, the quadrilateral is a parallelogram. The other properties vary.
In a kite ABCD with AB = AD and CB = CD, if angle BAD = 80°, angle BCD can be determined to be:
- A. 80°
- B. 100°
- C. 160°
- D. Cannot be determined without more information
Answer: D. Cannot be determined without more information
In a kite, knowing one angle is insufficient. The angles depend on the specific dimensions. Angle BCD cannot be uniquely determined from angle BAD alone.
In a kite, knowing one angle is insufficient. The angles depend on the specific dimensions. Angle BCD cannot be uniquely determined from angle BAD alone.
A quadrilateral has angles in the ratio 1:2:2:3. The largest angle is:
- A. 100°
- B. 120°
- C. 135°
- D. 150°
Answer: C. 135°
Let angles be x, 2x, 2x, 3x. Sum: x + 2x + 2x + 3x = 8x = 360°, so x = 45°. Largest angle = 3x = 135°.
Let angles be x, 2x, 2x, 3x. Sum: x + 2x + 2x + 3x = 8x = 360°, so x = 45°. Largest angle = 3x = 135°.