Step-by-step explanation:
2(x+7)=72 no, because this only changes the value on the right side. so this equation is not about the same equality anymore.
x+7=18 yes, because both sides were transformed by the same operation (division by 2). the equality is still maintained.
2x+7=36 no, because 2x+7 is NOT equal to 2(x+7). resolving 2(x+7) is 2x+14.
x+14=36 no, because again, x+14 is NOT equal to 2(x+7).
(2×x) + (2×7) = 36 yes, because the left side is a valid transformation of 2(x+7).
2x+14=36 yes, because the left side is a valid transformation of 2(x+7).
