9th Standard CBSE Syllabus & Materials
9th Standard CBSE
CBSE 9th Science Is matter around us pure? - New Model Questions Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Science Matter in our surroundings - New Model Questions Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Heron's Formula Sample Question Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Circles Sample Question Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Quadrilaterals Sample Question Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Triangles Sample Question Papers Study Material - QB365 Set A

Published on: 09/12/2019
Linear Equations in Two Variables
Download CBSE Class 9th Standard CBSE Mathematics question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 9th Standard CBSE Mathematics
Questions + Answers key
Take MCQ Mathematics Test

1.
Write four solutions for each of the following equations:
x=4y
2.
Express the following linear equation in the form ax+by+c=0 and indicate the values of a, b and c in each case:
x=3y
3.
Express the following linear equation in the form ax+by+c=0 and indicate the values of a, b and c in each case:
-2x+3y=6
4.
Solve for x: \(3x+11+{x\over2}=-{7\over2}+18.\)What will be the graph of this equation?
5.
Find the value of 'm' if x = 2, y = 1 is a solution of the equation 2x + 3y = m and represent it graphically
6.
Given the point (1, 2), find the equation of a line on which it lies. How many such equations are there?Write the equation in the form ax + by + c = 0.
7.
Find four different solutions of the equation x + 2y = 6
8.
Write the following equations in the form ax+by+c=0 and indicate the values of a, b and c
2x+3y=4.37
9.
Draw the graph of linear equations x+y=10 and 2x-y=5 and find the point of intersection.
10.
11.
Solve for x:
\(3x-12+{3\over7}x=2(x-1)\)
What type of graph is it in two dimensions?
12.
Determine the point on the graph of the equation 2x+5y=20 where x-coordinate is\({5\over2}\) times its ordinate.
13.
If x=-2, y=6 is solution of equation 3ax+2by=6 then find the value of b from 2(a-b)+2(3b-4)=4
14.
The sum of the ages of Apala and Meenu is 48.Write a linear equation in two variables to represent the statement.
x+y=48
x-y-10=0
2x+y=48
x+2y=48
15.
The equation y=3 in two variables can be written as:
1.x+1.y=3
0.x+1.y=3
0.x+0.y=3
1.x+0.y=3
16.
Write a, b, c for the equation 2x=5
2, 0, -5
0,2,-5
0,0,-5
2,0,5
17.
The condition that the equation ax+by+c=0 represents a linear equation in two variables is:
a≠0, b=0
b≠0, a=0
a=0, b=0
a≠0, b≠0
18.
The equation \(x+\sqrt{2}=0\) has
no solution
infinitely many solutions
only one solution
only two solution
1.
x=4y
\(\Rightarrow\ \ y={x\over 4}\)
Put x=0, we get \(y={0\over4}=0\)
Put x=4, we get \(y={4\over4}=1\)
Put x=-4, we get \(y={-4\over 4}=-1\)
Put x=2, we get \(y={2\over4}={1\over 2}\)
Four solutions are (0,0), (4, 1), (-4, -1) and \(\left(2,{1\over 2}\right)\)
2.
x=3y
x-3y+0=0
Comparing with ax+by+c=0, we get
a=1, b=-3, c=0.
3.
-2x+3y=6
Comparing with ax+by+c=0, we get
a=2, b=3, c=-6
4.
x=1
5.
m=7
6.
x+y=3; infinitely many; x+y-3=0
7.
By inspection, x = 2, y = 2 is a solution because for x = 2, y = 2
x + 2y = 2 + 4 = 6
Now, let us choose x = 0. With this value of x, the given equation reduces to 2y = 6 which has the unique solution y = 3. So x = 0, y = 3 is also a solution of x + 2y = 6. Similarly, taking y = 0, the given equation reduces to x = 6. So, x = 6, y = 0 is a solution of x + 2y = 6 as well. Finally, let us take y = 1. The given equation now reduces to x + 2 = 6, whose solution is given by x = 4. Therefore, (4, 1) is also a solution of the given equation. So four of the infinitely many solutions of the given equation are:
(2, 2), (0, 3), (6, 0) and (4, 1).
8.
2x+3y-4.37=0;
a=2, b=3 and c=-4.37
9.
x+y=10\(\Rightarrow\)y=10-x
| x | 0 | 2 | 3 | 4 | 5 |
| y | 10 | 8 | 7 | 6 | 5 |
2x-y=5
y=2x-5
| x | 0 | 2 | 5 |
| y | -5 | -1 | 5 |
Plot these point on the graph paper

10.

11.
\(3x-12+{3\over7}x=2(x-1)\)
\(\Rightarrow\ \ {24\over7}x-12=2x-2\)
\(\Rightarrow\ \ \ {24\over 7}x-2x=12-2\)
\(\Rightarrow\ \ \ {10x\over 7}=10\)
\(x=7\)
The graph of this equation is a line parallel to y-axis at a distance of 7 units to the right of origin O.
12.
2x+5y=20
\(x={5\over2}y\)
\(\therefore 2\left({5\over2},y\right)+5y=20\)
⇒ 10y=20
⇒ y=2
\(\therefore x={5\over 2}(2)=5\)
Hence the required point is (5, 2).
13.
If x=-2, y=6 is solution of equation
3ax+2by=6 then
3a(-2)+2b(6)=6
⇒ -6a+12b=6
⇒ -4+2b=1 ...(1)
Also,
2(a-1)+2(3b-4)=4
⇒ 2a-2+6b-8=4
⇒ 2a+6b=14
⇒ a+3b=7 ...(2)
Adding (1) and (2) we get
5b=8 ⇒ \(b={8\over 5}\)
Putting \(b={8\over 5}\) in (1), we get
-a+2\(\left(8\over 5\right)\)=1
\(\Rightarrow\ \ \ a={11\over5}-1={11\over 5}\)
Hence, \(a={11\over 5}, b={8\over 5}\)
14.
(a)
x+y=48
15.
Evident
16.
2x+0y-5=0
17.
definition
18.
(c)
only one solution
9th Standard CBSE Syllabus & Materials
9th Standard CBSE
CBSE 9th Mathematics Lines and Angles Sample Question Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Introduction to Euclid's Geometry Sample Question Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Linear Equations in Two Variables Sample Question Papers Study Material - QB365 Set A
NEW9th Standard CBSE
CBSE 9th Mathematics Coordinate Geometry Sample Question Papers Study Material - QB365 Set A
CBSE 9th Standard CBSE Subjects
CBSE Standards