Chapter 3: Pair of Linear Equations in Two Variables
Unique Previous Year Questions extracted from the CBSE Class 10 Basic Mathematics 2025 question paper sets, with major conceptual variations retained.
I
Multiple Choice Questions
1. Solution Identification
1 Mark
The number of solutions of the system of equations
\[
x=3,\qquad y=-1
\]
is:
Set 430/2/2
2. Parallel Lines – Number of Solutions
1 Mark
The number of solutions of the system of equations
\[
x=a,\qquad x=b
\]
where \(a\neq b\), is:
Set 430/2/3
3. Finding the Constant
1 Mark
If \((0,0)\) is the solution of the equation
\[
x+y=c-1,
\]
then the value of \(c\) is:
Set 430/2/1
4. Unique Solution Condition
1 Mark
For what value(s) of \(k\) does the system of equations
\[
kx+2y=3
\]
and
\[
2x+y=5
\]
have a unique solution?
Set 430/3/1
5. Parallel Lines Condition
1 Mark
The value of \(m\) for which the lines
\[
14x+my=20
\]
and
\[
-3x+2y=16
\]
are parallel, is:
Set 430/4/2
6. Consistency Nature
1 Mark
The system of linear equations given by
\[
x=a,\qquad y=b
\]
is:
Set 430/3/3
II
Assertion – Reason Question
7. Consistency and Infinitely Many Solutions
1 Mark
Assertion (A):
The value of \(p\) for which the system of equations
\[
4x+py+8=0
\]
and
\[
2x+2y+2=0
\]
is consistent is \(4\).
Reason (R):
The system of equations
\[
a_1x+b_1y=c_1
\]
and
\[
a_2x+b_2y=c_2
\]
is consistent with infinitely many solutions if
\[
\frac{a_1}{a_2}
=
\frac{b_1}{b_2}
=
\frac{c_1}{c_2}.
\]
III
Very Short Answer Type Questions
8. Algebraic Solution – Fractions
2 Marks
Solve the following system of equations for \(x\) and \(y\):
\[
\frac{x}{2}+\frac{2y}{3}=-1
\]
\[
x-\frac{y}{3}=3
\]
Set 430/1/1
9. Algebraic Solution – Decimals
2 Marks
Solve for \(x\) and \(y\):
\[
0.1x+0.3y=1
\]
\[
0.2x-0.1y=-0.1
\]
Set 430/1/2
10. Infinitely Many Solutions
2 Marks
Find the value of \(c\) for which the following pair of linear
equations has infinitely many solutions:
\[
cx+3y=c-3
\]
\[
12x+cy=c
\]
Set 430/2/1
11. Arithmetic Solution
2 Marks
Solve for \(x\) and \(y\):
\[
3x+2y=65
\]
\[
2x+3y=60
\]
Set 430/2/1
12. Graphical Solution
2 Marks
Solve the following system of equations graphically:
\[
x+2y=10
\]
\[
y=3
\]
Set 430/3/2
13. Graphical Solution
2 Marks
Solve the following system of linear equations graphically:
\[
x+y=5
\]
\[
x-y=3
\]
Set 430/3/3
IV
Short Answer Type Questions
14. Graphical Solution – Intersecting Lines
3 Marks
Solve the following system of equations graphically:
\[
x+3y=6
\]
\[
2x-3y=12
\]
Set 430/1/2
15. Word Problem – Complementary Angles
3 Marks
\(x\) and \(y\) are complementary angles such that
\[
x:y=1:2.
\]
Express the given information as a system of linear equations
in two variables and hence solve it.
Set 430/1/2
16. Graphical Intercepts
3 Marks
Solve graphically the following pair of linear equations:
\[
2x-y=2
\]
\[
4x-y=4
\]
Also, write the coordinates of the points where the lines
represented by these equations cut the \(y\)-axis.
Set 430/2/1
17. Word Problem – Cricket Coaching
3 Marks
An academy provided 10 bats and 5 balls for ₹32,500.
Later, it bought 2 bats and 8 balls for ₹10,000.
If the price remained the same, find the cost of 1 bat and 1 ball.
Set 430/2/2
If the price remained the same, find the cost of 1 bat and 1 ball.
18. Word Problem – Fraction
3 Marks
A fraction becomes
\[
\frac{1}{3},
\]
when 1 is subtracted from the numerator and it becomes
\[
\frac{1}{4},
\]
when 8 is added to its denominator.
Find the fraction.
Set 430/3/1
Find the fraction.
19. Unknown \(k\) and Solutions
3 Marks
Find the value of \(k\) for which the following pair of linear
equations will have infinitely many solutions:
\[
kx+3y-(k-3)=0
\]
\[
12x+ky-k=0
\]
Hence, find any two solutions of the given pair of equations.
Set 430/3/1
V
Long Answer Type Questions
20. Graphical Analysis
5 Marks
Determine graphically whether the following pair of linear
equations has a unique solution or infinitely many solutions:
\[
2x+3y=12
\]
\[
x-y=1
\]
Set 430/5/1
21. Word Problem – Number Digits
5 Marks
The sum of a 2-digit number and the number obtained by reversing
the order of its digits is 121. The two digits differ by 3.
(i)
Represent the information in the form of a pair of linear equations.
(ii)
Show that the equations have a unique solution.
(iii)
Solve the equations and find the number.
22. Graphical Solution – General
5 Marks
Solve the following pair of equations using graphical method:
\[
3x-4y+3=0
\]
\[
-2x+5y=9
\]
Set 430/5/3
23. Word Problem – Investment and Interest
5 Marks
Nidhi received simple interest of ₹1,200 when she invested
₹\(x\) at 6% p.a. and ₹\(y\) at 5% p.a. for 1 year.
Had she invested ₹\(x\) at 3% p.a. and ₹\(y\) at 8% p.a. for that year, she would have received simple interest of ₹1,260.
Find the values of \(x\) and \(y\).
Set 430/6/2
Had she invested ₹\(x\) at 3% p.a. and ₹\(y\) at 8% p.a. for that year, she would have received simple interest of ₹1,260.
Find the values of \(x\) and \(y\).
24. Graphical Solution – Extended
5 Marks
Solve the following pair of linear equations by graphical method:
\[
2x+y=9
\]
\[
x-2y=2
\]
Set 430/6/3