The firts step to solving this problem would be to group like terms which is the same as C: Collect like terms so it's not C. It's also not D because that is also kind of the same thing because we only collected the terms on on side. We also have to isolate the variable.
7x+15-15=24+4x-15
7x=4x+9
7x-4x=4x+9-4x
3x=9
Divide by 3 on both sides
x=3
The only thing we didn't do was use distrubituve property. So the answer is A
