Answer:
x=9
Explanation:
x + 3(2x - 5) = 4x – 12
distrubute left side
3 times 2x; 3 times -5
x+6x-15=4x-12
add like terms
x+6x
7x-15=4x-12
get all variables on the same side
7x-15=4x-12
-4x -4x
3x-15=12
add 15 to both sides
3x-15=12
+15 +15
3x=27
divide by 3 on both sides
3x/3=27/3
x=9