Help me please I will give brainleist

? = 7x

Step-by-step explanation:

Lets simplify the equation first;

5x - 20 + ? = -20 + 12x

=> So now, we have to make the equation on the left equation congruent to the right equation:

It we already have -20 common on both sides, but we need to find out, what added by 5x gives us 12x,

=> So we can let the number we have to find out be y, and say:

5x + y = 12x

=> y = 12x - 5x

=> y = 7x

Therefore, ? = 7x

Hope this helps!

step-by-step explanation:

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.