Page 21 - Mathematics Class - X

Viva-Voce

1. What is the most general form of a pair of linear equations in two variables?
Ans. a x + b y + c = 0 and a x + b y + c = 0
1 1 1 2 2 2
2. What is the degree of variable in a linear equation?
Ans. The degree of variable is 1.

3. How many solutions a pair of linear equation can have?
Ans. A pair of linear equation can have two solutions.

4. What kind of a solution does pair of linear equations have, if their graphs are parallel lines?
Ans. These equations have no solution and such pair of linear equations are called inconsistent.
5. Name the methods by which a pair of linear equations in two variables can be solved.

Ans. A pair of linear equations can be solved by:
(i) graphical method

(ii) algebraic method

MCQs

1. Which of the following is not a linear equation?

a) 4x + 6y + 9 = 0 b) 7x + 3y – 10 = 0 c) x + y + 2 = 0 d) 4x + 6x + 9 = 0
2
2. The degree of variable in the linear equation is

a) 1 b) 2 c) 3 d) 0
3. If the lines are parallel, then the pair of equations has
a) Infinitely many solutions b) No solution

c) One solution d) None of these
4. If the lines coincide, then the pair of equations has

a) Infinitely many solutions b) No solution
c) One solution d) None of these
5. If the lines intersect at a point, then the pair of equations has

a) Infinitely many solutions b) No solution
c) Unique solution d) None of these

Answers: 1. d) 4x + 6x + 9 = 0 2. a) 1 3. b) No solution
2
4. a) Infinitely many solutions 5. c) Unique solution

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