Question

1. $2x + 7 - 5x + 8 = 3(5 + 6x) - 12x$

Explanation:

Step1: Combine like terms left side

$2x - 5x + 7 + 8 = -3x + 15$

Step2: Expand right side

$3\times5 + 3\times6x - 12x = 15 + 18x - 12x$

Step3: Simplify right side

$15 + (18x - 12x) = 15 + 6x$

Step4: Set sides equal, isolate x terms

$-3x + 15 = 15 + 6x$
$-3x - 6x = 15 - 15$

Step5: Solve for x

$-9x = 0$
$x = \frac{0}{-9}$

Answer:

$x = 0$