−4(5 − 3x) = 12x + 20
Solve for x:
First use the Distributive property:
-20 + 12x = 12x +20
Add 20 to both sides:
12x =12x + 40
Now you can't get X by itself, because both sides of the equation have the same quantity of x ( they both have 12x).
This means there is no solution.