## anonymous 5 years ago √x^2negativex-12=x+3

1. watchmath

$$\sqrt{x^2-x-12}=x+3$$ like that?

2. anonymous

yes :)

3. anonymous

When I tried putting the negative sign in front of the x and then minusing the 12 it thought I was trying to subtract the x

4. watchmath

$$\sqrt{(x+3)(x-4)}=(x+3)$$ Square both sides $$(x+3)(x-4)=(x+3)(x+3)$$ $$(x+3)((x-4)-(x+3))=0$$ $$(x+3)(-7)=0$$ Hence $$x=-3$$ is the only answer.

5. anonymous

Thank you !!!