Question

Solve for x. 2x + 6 – 6x = 30
A. –6
B. –3
C. 3
D. 6

Answer 1

So,

2x + 6 - 6x = 30

Collect Like Terms.
-4x + 6 = 30

Subtract 6 from both sides.
-4x = 24

Divide both sides by -4.
x = -6

Check.
2x + 6 - 6x = 30
2(-6) + 6 - 6(-6) = 30
-12 + 6 + 36 = 30
-6 + 36 = 30
30 = 30 This checks.

S = {-6}

That is option A.