Page 24 - Mathematics Class - X

Viva-Voce

1. What is the maximum number of real roots of a quadratic equation?
Ans. The maximum number of real roots of a quadratic equation are two.

2. What is the condition for a quadratic equation to have no real roots?
Ans. A quadratic equation will have no real roots, if b – 4ac < 0.
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3. What is the condition for a quadratic equation to have two distinct real roots?

Ans. If b – 4ac > 0, then a quadratic equation will have two distinct real roots.
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4. Is y = 6 a quadratic equation?
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Ans. Yes, it is a quadratic equation because degree of variables (y) is two.
5. How will you identify a given equation as a quadratic equation?
Ans. A quadratic equation in the variable x, is of the form ax + bx + c = 0, where a, b and c are real numbers and
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a ≠ 0.

6. What is the shape of the graph of a quadratic polynomial?
Ans. Parabola
7. If the degree of a polynomial is more than 1. Is it a linear polynomial?

Ans. No
8. If the roots of the equation ax + bx + c = 0 are equal, then what will be the value of c ?
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Ans. b /4a
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MCQs

1. Which of the following is not a quadratic equation?
a) 4x = 2 b) 3y – 10 = 0 c) x + y + 2 = 0 d) 9x + 9 = 0
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2. ________ is also called the solution of a quadratic equation.
a) x 2 b) y 2 c) z 2 d) a
3. Any quadratic equation can have at most ________ roots.

a) Two b) Three c) Four d) Zero
4. A quadratic equation will have two distinct real roots if

a) b – 4ac = 0 b) b – 4ac > 0 c) b – 4ac ≠ 0 d) None of these
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5. If the constant term is 0, then one of the roots of the given equation will be
a) One b) Two c) Zero d) Four

Answers: 1. c) x + y + 2 = 0 2. d) a 3. a) Two
4. b) b – 4ac > 0 5. c) Zero
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