Verified Answer :

3x + 7 = x - 15

First, make sure to subtract \(x\) from both sides.
\(3x + 7 - x = -15\)
Second, simplify 3x - x to get 2x, and then keep the 7.
\(2x + 7 = -15\)
Third, subtract \(7\) from both sides. 
\(2x = -15 - 7\)
Fourth, simplify -15 - 7 to get -22.
\(2x = -22\)
Fifth, take the 2 and divide both sides by it, keeping the \(x\) by itself.
\(x = - \frac{22}{2}\)
Sixth, since 11 goes into 2 to get 22, simplify the fraction to 11.
\(x = -11\)

Answer: x = -11