Verified answer

3 – 3(x – 2b) = ax + 4

First multiply -3 by x-2b

3-3x+6b = ax+4

Now isolate the terms that have x in them

Add 3x to both sides

3+6b = ax+4+3x

Subtract 4 from both sides

6b-1 = ax+3x

Factor out x on the RHS

6b-1 = x(3+a)

Now divide both sides by (3+a)

(6b-1)/(3+a) = x