Answer:
x = 78 / 5
Explanation:
The series of calculation to get x would be:
1st : Multiply both sides by 5.
(1/5)(5x + 12) * 5 = 18 * 5
5x + 12 = 90
2nd : Transfer 12 to right side, therefore subtracting it.
5x = 90 – 12
5x = 78
3rd : Divide both sides by 5.
5x / 5 = 78 / 5
x = 78 / 5