Question

Mary is solving the equation:

3(x + 4)= 7x - 20.
The first thing she does is rewrite the equation shown below. Which property did Mary use to get from the original equation to her rewritten equation? 3x + 12= 7x - 20. Please explain your answer to the question and start operations used to describe the property choice.

Answer 1

Mary used the distributive property to rewrite the equation.

Step-by-step explanation:

Mary used the distributive property to rewrite the equation. The distributive property states that for any real numbers a, b, and c, a(b + c) = ab + ac. In this case, Mary distributed the 3 to both terms inside the parentheses (x and 4) to get 3x + 12. The rest of the equation remains unchanged.