PPT: Linear Equations in Two Variables | Mathematics (Maths) Class 9 PDF Download

 Page 1


L i n e a r
E q u a t i o n s
Exploring linear equations
with Two variable
Page 2


L i n e a r
E q u a t i o n s
Exploring linear equations
with Two variable
Based on number of
variables used , they can
be categorised. Like
linear equation in one
variable and two variable.
Linear Equations
To keep things balanced, we
need to add or subtract the
same number on both sides
of the equation. 
R e m e m b e r :
An equation in which
the maximum power of
the variable is one
These equations can be used to solve real-
life problems like 
Finding the cost of pencils, 
Weather predictions, 
Expressing cricket scores, 
And even deciding how many chocolates
and balloons you can buy with your
money. 
The government also uses linear
equations for surveys.
Page 3


L i n e a r
E q u a t i o n s
Exploring linear equations
with Two variable
Based on number of
variables used , they can
be categorised. Like
linear equation in one
variable and two variable.
Linear Equations
To keep things balanced, we
need to add or subtract the
same number on both sides
of the equation. 
R e m e m b e r :
An equation in which
the maximum power of
the variable is one
These equations can be used to solve real-
life problems like 
Finding the cost of pencils, 
Weather predictions, 
Expressing cricket scores, 
And even deciding how many chocolates
and balloons you can buy with your
money. 
The government also uses linear
equations for surveys.
Linear Equations
in Two variables
ax + by + c = 0
where a, b, and c
are real numbers,
and a and b are
not both zero.
Example:
(i) 3x + 2y - 5 = 0
a = 3
b = 2
c = -5
variables are x and y.
Page 4


L i n e a r
E q u a t i o n s
Exploring linear equations
with Two variable
Based on number of
variables used , they can
be categorised. Like
linear equation in one
variable and two variable.
Linear Equations
To keep things balanced, we
need to add or subtract the
same number on both sides
of the equation. 
R e m e m b e r :
An equation in which
the maximum power of
the variable is one
These equations can be used to solve real-
life problems like 
Finding the cost of pencils, 
Weather predictions, 
Expressing cricket scores, 
And even deciding how many chocolates
and balloons you can buy with your
money. 
The government also uses linear
equations for surveys.
Linear Equations
in Two variables
ax + by + c = 0
where a, b, and c
are real numbers,
and a and b are
not both zero.
Example:
(i) 3x + 2y - 5 = 0
a = 3
b = 2
c = -5
variables are x and y.
x
x
x
x
x x
x
x
x
x
y
y
y
y
y
1
1
+ + -
Can you form an
expression for this model? 
Page 5


L i n e a r
E q u a t i o n s
Exploring linear equations
with Two variable
Based on number of
variables used , they can
be categorised. Like
linear equation in one
variable and two variable.
Linear Equations
To keep things balanced, we
need to add or subtract the
same number on both sides
of the equation. 
R e m e m b e r :
An equation in which
the maximum power of
the variable is one
These equations can be used to solve real-
life problems like 
Finding the cost of pencils, 
Weather predictions, 
Expressing cricket scores, 
And even deciding how many chocolates
and balloons you can buy with your
money. 
The government also uses linear
equations for surveys.
Linear Equations
in Two variables
ax + by + c = 0
where a, b, and c
are real numbers,
and a and b are
not both zero.
Example:
(i) 3x + 2y - 5 = 0
a = 3
b = 2
c = -5
variables are x and y.
x
x
x
x
x x
x
x
x
x
y
y
y
y
y
1
1
+ + -
Can you form an
expression for this model? 
x
x
x
x
x x
x
x
x
x
y
y
y
y
y
1
1
+ + -
Simplifying Linear Expressions