Answer: no not less than 23
Depends on where you are in the math book but this would be the most simple way.
n= number
sqar(-1) = i
3x + 7 = x
First, subtract 3x from both sides. / Your problem should look like: 7 = x - 3x
Second, simplify x - 3x to -2x. / Your problem should look like: 7 = -2x
Third, divide both sides by -2. / Your problem should look like:

= x
Fourth, simplify

to

/ Your problem should look like:

= x
Fifth, switch sides. / Your problem should look like: x =

Answer as fraction:

Answer as decimal: -3.5