Step 1. Expand
-12x - 9 + 24x + 4 = 43
Step 2. Simplify -12x - 9 + 24x + 4 to 12x - 5
12x - 5 = 43
Step 3. Add 5 to both sides
12x = 43 + 5
Step 4. Simplify 43 + 5 to 48
12x = 48
Step 5. Divide both sides by 12
x = 48/12
Step 6. Simplify 48/12 to 4
x = 4