CBSE Class 7 Answered
Steps to solve a linear equation:
● Transfer all the x terms (that is all variable terms) on one side, and keep the numbers
to the other side.
● Simplify each side and solve for x.
● Verify to be sure whether the answers satisfy the original equations.
Example:
Solve the equation 6(3x + 2) + 5(7x - 6) - 12x = 5(6x - 1) + 6(x - 3) and verify your answer
Solution:
6(3x + 2) + 5(7x - 6) - 12x = 5(6x - 1) + 6(x - 3)
⇒ 18x + 12 + 35x - 30 - 12x = 30x - 5 + 6x - 18
⇒ 18x + 35x - 12x + 12 - 30 = 30x + 6x - 5 - 18
⇒ 41x - 18 = 36x - 23
⇒ 41x - 36x = - 23 + 18
⇒ 5x = -5
⇒ x = -1
Therefore, x = -1 is the solution of the given equation.
Verification:
L.H.S. = 6(3x + 2) + 5(7x - 6) - 12x
Substitute the value of x = -1 we get;
= 6[3 × (-1) + 2] + 5 [7 × (-1) - 6] - 12 × (-1)
= 6[-3 + 2] + 5[-7 - 6] + 12
= 6 × (-1) + 5 (-13) + 12
= - 6 - 65 + 12
= -71 + 12
= -59
Verification:
R.H.S. = 5(6x - 1) + 6(x - 3)
Substitute the value of x = - 1, we get
= 5[6 × (-1) - 1] + 6[(-1) - 3]
= 5(-6 - 1) + 6(-1 -3)
= 5 × (-7) + 6 × (-4)
= - 35 - 24
= - 59
Since, L.H.S. = R.H.S. hence verified.