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MCQ Questions for Class 10 Maths Quadratic Equations with Answers

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Free PDF Download of CBSE Class 10 Math Quadratic Equations Multiple Choice Questions with Answers. Maths Multiple Choice Questions with Answers for Class 10 are Prepared Based on Latest Exam Pattern. Students can solve  mcq questions for class 10 maths Pair of Linear Equations in Two Variables to know their preparation level.

Class 10 Maths MCQ Chapter 4 Quadratic Equations

1. Which of the following is not a quadratic equation
(a) x² + 3x – 5 = 0
(b) x² + x3 + 2 = 0
(c) 3 + x + x² = 0
(d) x² – 9 = 0

Answer/ Explanation

Answer: b
Explaination:Reason: Since it has degree 3.

 


2. The quadratic equation has degree
(a) 0
(b) 1
(c) 2
(d) 3

Answer/ Explanation

Answer: c
Explaination:Reason: A quadratic equation has degree 2.

 


3. The cubic equation has degree
(a) 1
(b) 2
(c) 3
(d) 4

Answer/ Explanation

Answer: c
Explaination:Reason: A cubic equation has degree 3.

 


4. A bi-quadratic equation has degree
(a) 1
(b) 2
(c) 3
(d) 4

Answer/ Explanation

Answer: d
Explaination:Reason: A bi-quadratic equation has degree 4.

 


5. The polynomial equation x (x + 1) + 8 = (x + 2) {x – 2) is
(a) linear equation
(b) quadratic equation
(c) cubic equation
(d) bi-quadratic equation

Answer/ Explanation

Answer: a
Explaination:Reason: We have x(x + 1) + 8 = (x + 2) (x – 2)
⇒ x² + x + 8 = x² – 4
⇒ x² + x + 8- x² + 4 = 0
⇒ x + 12 = 0, which is a linear equation.

 


6. The equation (x – 2)² + 1 = 2x – 3 is a
(a) linear equation
(b) quadratic equation
(c) cubic equation
(d) bi-quadratic equation

Answer/ Explanation

Answer: b
Explaination:Reason: We have (x – 2)² + 1 = 2x – 3
⇒ x² + 4 – 2 × x × 2 + 1 = 2x – 3
⇒ x² – 4x + 5 – 2x + 3 = 0
∴ x² – 6x + 8 = 0, which is a quadratic equation.

 


7. The roots of the quadratic equation 6x² – x – 2 = 0 are
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 1

Answer/ Explanation

Answer: c
Explaination:Reason: We have 6×2 – x – 2 = 0
⇒ 6x² + 3x-4x-2 = 0
⇒ 3x(2x + 1) -2(2x + 1) = 0
⇒ (2x + 1) (3x – 2) = 0
⇒ 2x + 1 = 0 or 3x – 2 = 0
∴ x =-\frac{1}{2}, x = \frac{2}{3}

 


8. The quadratic equation whose roots are 1 and
(a) 2x² + x – 1 = 0
(b) 2x² – x – 1 = 0
(c) 2x² + x + 1 = 0
(d) 2x² – x + 1 = 0

Answer/ Explanation

Answer: b
Explaination:Reason: Required quadratic equation is
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 7

 


9. The quadratic equation whose one rational root is 3 + √2 is
(a) x² – 7x + 5 = 0
(b) x² + 7x + 6 = 0
(c) x² – 7x + 6 = 0
(d) x² – 6x + 7 = 0

Answer/ Explanation

Answer: d
Explaination:Reason: ∵ one root is 3 + √2
∴ other root is 3 – √2
∴ Sum of roots = 3 + √2 + 3 – √2 = 6
Product of roots = (3 + √2)(3 – √2) = (3)² – (√2)² = 9 – 2 = 7
∴ Required quadratic equation is x² – 6x + 7 = 0

 


10. The equation 2x² + kx + 3 = 0 has two equal roots, then the value of k is
(a) ±√6
(b) ± 4
(c) ±3√2
(d) ±2√6

Answer/ Explanation

Answer: d
Explaination:Reason: Here a = 2, b = k, c = 3
Since the equation has two equal roots
∴ b² – 4AC = 0
⇒ (k)² – 4 × 2 × 3 = 0
⇒ k² = 24
⇒ k = ± √24
∴ k= ± \pm \sqrt{4 \times 6} = ± 2√6

 


11. The roots of the quadratic equation x+\frac{1}{x}=3, x ≠ 0 are.
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 2

Answer/ Explanation

Answer: c
Explaination:Reason: We have x+\frac{1}{x}=3
\frac{x^{2}+1}{x}=3
⇒ x² + 1 = 3x
On comparing with ax² + bx + c = 0
∴ a = 1, b = – 3, c = 1
⇒ D = b² – 4ac = (-3)² – 4 × (1) × (1) = 9 – 4 = 5

 


12. The roots of the quadratic equation 2x² – 2√2x + 1 = 0 are
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 3

Answer/ Explanation

Answer: c
Explaination:Reason: Here a = 2, b = -2√2 , c = 1
∴ D = b² – 4ac = (-2√2 )² – 4 × 2 × 1 = 8 – 8 = 0
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 8

 


13. The sum of the roots of the quadratic equation 3×2 – 9x + 5 = 0 is
(a) 3
(b) 6
(c) -3
(d) 2

Answer/ Explanation

Answer: c
Explaination:Reason: Here a = 3, b = -9, c = 5
∴ Sum of the roots =\frac{-b}{a}=-\frac{(-9)}{3}=3

 


14. If the roots of ax2 + bx + c = 0 are in the ratio m : n, then
(a) mna² = (m + n) c²
(b) mnb² = (m + n) ac
(c) mn b² = (m + n)² ac
(d) mnb² = (m – n)² ac

Answer/ Explanation

Answer: c
Explaination:
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 9

 


15. If one root of the equation x² + px + 12 = 0 is 4, while the equation x² + px + q = 0 has equal roots, the value of q is
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 4

Answer/ Explanation

Answer: a
Explaination:Reason: Since 4 is a root of x² + px + 12 = 0
∴ (4)² + p(4) + 12 = 0
⇒ p = -7
Also the roots of x² + px + q = 0 are equal, we have p² – 4 x 1 x q = 0
⇒ (-7)² -4q = 0
\therefore q=\frac{49}{4}

 


16. a and p are the roots of 4x² + 3x + 7 = 0, then the value of \frac{1}{\alpha}+\frac{1}{\beta} is
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 5

Answer/ Explanation

Answer: b
Explaination:
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 10

 


17. If a, p are the roots of the equation (x – a) (x – b) + c = 0, then the roots of the equation (x – a) (x – P) = c are
(a) a, b
(b) a, c
(c) b, c
(d) none of these

Answer/ Explanation

Answer: a
Explaination:Reason: By given condition, (x – a) (x – b) + c = (x – α) (x – β)
⇒ (x – α) (x – β) – c = (x – a) (x – b)
This shows that roots of (x – α) (x – β) – c are a and b

 


18. Mohan and Sohan solve an equation. In solving Mohan commits a mistake in constant term and finds the roots 8 and 2. Sohan commits a mistake in the coefficient of x. The correct roots are
(a) 9,1
(b) -9,1
(c) 9, -1
(d) -9, -1

Answer/ Explanation

Answer: a
Explaination:Reason: Correct sum = 8 + 2 = 10 from Mohan
Correct product = -9 x -1 = 9 from Sohan
∴ x² – (10)x + 9 = 0
⇒ x² – 10x + 9 = 0
⇒ x² – 9x – x + 9
⇒ x(x – 9) – 1(x – 9) = 0
⇒ (x-9) (x-l) = 0 .
⇒ Correct roots are 9 and 1.

 


19. If a and p are the roots of the equation 2x² – 3x – 6 = 0. The equation whose roots are \frac{1}{\alpha} and \frac{1}{\beta} is
(a) 6x² – 3x + 2 = 0
(b) 6x² + 3x – 2 = 0
(c) 6x² – 3x – 2 = 0
(d) x² + 3x-2 = 0

Answer/ Explanation

Answer: b
Explaination:
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 11

 


20. If the roots of px2 + qx + 2 = 0 are reciprocal of each other, then
(a) P = 0
(b) p = -2
(c) p = ±2
(d) p = 2

Answer/ Explanation

Answer: d
Explaination:Reason: here α = \frac{1}{β}
∴ αβ = 1
\frac{2}{p} = 1
∴ p = 2

 


21. If one root of the quadratic equation 2x² + kx – 6 = 0 is 2, the value of k is
(a) 1
(b) -1
(c) 2
(d) -2

Answer/ Explanation

Answer: b
Explaination:Reason: Scice x = 2 is a root of the equation 2x² + kx -6 = 0
∴ 2(2)² +k(2) – 6 = 0
⇒ 8 + 2k – 6 = 0
⇒ 2k = -2
∴ k = -1

 


22. The roots of the quadratic equation
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 6
(a) a, b
(b) -a, b
(c) a, -b
(d) -a, -b

Answer/ Explanation

Answer: d
Explaination:
MCQ Questions for Class 10 Maths Quadratic Equations with Answers 12

 


23. The roots of the equation 7x² + x – 1 = 0 are
(a) real and distinct
(b) real and equal
(c) not real
(d) none of these

Answer/ Explanation

Answer: a
Explaination:Reason: Here a = 2, b = 1, c = -1
∴ D = b² – 4ac = (1)² – 4 × 2 × (-1) = 1 + 8 = 9 > 0
∴ Roots of the given equation are real and distinct.

 


24. The equation 12x² + 4kx + 3 = 0 has real and equal roots, if
(a) k = ±3
(b) k = ±9
(c) k = 4
(d) k = ±2

Answer/ Explanation

Answer: a
Explaination:Reason: Here a = 12, b = 4k, c = 3
Since the given equation has real and equal roots
∴ b² – 4ac = 0
⇒ (4k)² – 4 × 12 × 3 = 0
⇒ 16k² – 144 = 0
⇒ k² = 9
⇒ k = ±3

 


25. If -5 is a root of the quadratic equation 2x² + px – 15 = 0, then
(a) p = 3
(b) p = 5
(c) p = 7
(d) p = 1

Answer/ Explanation

Answer: c
Explaination:Reason: Since – 5 is a root of the equation 2x² + px -15 = 0
∴ 2(-5)² + p (-5) – 15 = 0
⇒ 50 – 5p -15 = 0
⇒ 5p = 35
⇒ p = 7

 


26. If the roots of the equations ax² + 2bx + c = 0 and bx² – 2√ac x + b = 0 are simultaneously real, then
(a) b = ac
(b) b2 = ac
(c) a2 = be
(d) c2 = ab

Answer/ Explanation

Answer: b
Explaination:Reason: Given equations have real roots, then
D1 ≥ 0 and D2 ≥ 0
(2b)² – 4ac > 0 and (-2√ac)² – 4b.b ≥ 0
4b² – 4ac ≥ 0 and 4ac – 4b2 > 0
b² ≥ ac and ac ≥ b²
⇒ b² = ac

 


27. The roots of the equation (b – c) x² + (c – a) x + (a – b) = 0 are equal, then
(a) 2a = b + c
(b) 2c = a + b
(c) b = a + c
(d) 2b = a + c

Answer/ Explanation

Answer: d
Explaination:Reason: Since roots are equal
∴ D = 0 => b² – 4ac = 0
⇒ (c – a)² -4(b – c) (a – b) = 0
⇒ c² – b² – 2ac -4(ab -b² + bc) = 0 =>c + a-2b = 0 => c + a = 2b
⇒ c² + a² – 2ca – 4ab + 4b² + 4ac – 4bc = 0
⇒ c² + a² + 4b² + 2ca – 4ab – 4bc = 0
⇒ (c + a – 2b)² = 0
⇒ c + a – 2b = 0
⇒ c + a = 2b

 


28. A chess board contains 64 equal squares and the area of each square is 6.25 cm². A border round the board is 2 cm wide. The length of the side of the chess board is
(a) 8 cm
(b) 12 cm
(c) 24 cm
(d) 36 cm

Answer

Answer: c

 


29. One year ago, a man was 8 times as old as his son. Now his age is equal to the square of his son’s age. Their present ages are
(a) 7 years, 49 years
(b) 5 years, 25 years
(c) 1 years, 50 years
(d) 6 years, 49 years

Answer

Answer: a

 


30. The sum of the squares of two consecutive natural numbers is 313. The numbers are
(a) 12, 13
(b) 13,14
(c) 11,12
(d) 14,15

Answer

Answer: a

 


We hope the MCQ Questions for Class 10 Maths Quadratic Equations with Answers with Solutions, help you. If you have any query regarding Maths Class 10 Maths MCQ Chapter 4 Quadratic Equations with Solutions, drop a comment below and we will get back to you at the earliest.

The post MCQ Questions for Class 10 Maths Quadratic Equations with Answers appeared first on Learn CBSE.


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