The expression is .

According to subtraction property of equality: if , then .

         (Subtract 5 from each side)

                    (Additive inverse property: )

x = 13                          (Subtract: )

Check:

To check the solution Substitute the value of x = 13 in above expression.

18 = 18                       (Add: 13 + 5 = 18)

The value of x = 13

By the number line x = 13