## anonymous one year ago If y = (x + 3)2, then (-2x - 6)2 must equal which of the following? A. -4y2 B. -2y2 C. -4y D. 4y wHAT FORMULA DO I USE TO GET THE ANSWER?

1. anonymous

Does anyone know what formula I use to get the answer?

2. anonymous

You use math... $y = (x+3)^2$ $\sqrt(y) = x+3$ $(-2x-6)^2 = (-2\sqrt(y))^2$ =4y (...gotta learn how to write latex again)

3. anonymous

@nphuongsun93 Thank can you walk me through the steps so I know how to do it with other problems?

4. anonymous

Ok. $y = (x+3)^2$$\sqrt(y) = x+3$ Understand this so far?

5. jdoe0001

hint: $$y={\color{brown}{ (x+3)^2 }}\qquad (-2x-6)^2\to \begin{cases} [-2(x+3)]^2\impliedby \textit{common factor}\\ (-2)^2(x+3)^2\impliedby expanded\\ +4{\color{brown}{ (x+3)^2 }} \end{cases}$$