Question

9. On Johnny math test, he was asked to re-write the expression –3(x + 10) by using the distributive

property. Below is Johnny's answer. Is his answer correct? Explain.

Original Expression:
-3(x + 10)

Johnny's answer: 3x – 30

Answer 1

No, he is incorrect because he forgot to multiple the negative by the x, and only multiplied 3 by x instead of -3 by x.

Explanation:

The correct re-write of this expression is:

-3x - 30