MEAP Preparation - Grade 7 Mathematics 2.95 Domain of a Variable

The domain of a variable is a set of values that the variable can assume (take).

Example: Solve the equation x+5(x+2) = 22, given that the domain of the variable is {1,2,3,....}. Solution:

Value of x

L.H.S

R.H.S

1

1+5(1+2)=16

22

2

2+5(2+2)=22

22

3

3+5(3+2)=28

22

From the above table we observe that when x=2, L.H.S=R.H.S. Therefore, x=2 is the root of the given equation.
Directions: Find the LHS and RHS of the equation given in each question using different values of the variable. Then find the root of the equation and enter it in the space provided.