2. Linear equation in one variable:
An equation of one variable and first order is called a
linear equation in one variable such an equation has
only one solution. A solution is also called the ‘root’ of
the given equation. An equation that can be written in
the form,
ax + b = 0,
Where a and b are real numbers and a ≠ o.
Following are some examples:
a) 2x + 3 = 0
x 1 2
b)
3 2 3
+ =
c) 5(3x+2) - 2 = - 2(1-7x)
3. Example-1
Solve the equation x – 4 = 5.
Solution:
Since x – 4 = 5
x = 5 + 4
x = 9
Example-2
Solve the equation 3x – 4 = 5.
Solution:
Since 3x – 4 = 5
3x = 5 + 4
3x = 9
9
x
3
=
x = 3
4. Example-3
Solve the equation 3-{2(1-x)-x} = 4
Solution:
Since 3-{2(1-x)-x} = 4
3-{2-2x-x} = 4
3-(2-3x) = 4
3-2+3x = 4
1+3x = 4
3x = 4-1
3x = 3
3
x
3
=
x = 1