15x2 - 56 equals 88 plus 6x2?

Answer 1

15x2 - 56 = 88 + 6x2

Subtract 6x2 from each side:

9x2 - 56 = 88

Add 56 to each side:

9x2 = 144

Divide each side by 9:

x2 = 144/9

Take the square root of each side:

x = 12/3 = 4

x = -4