## anonymous 5 years ago √(9x+67) =x+5 solve

1. anonymous

square both sides. $9x+67=(x+5)^2$ $9x+67=x^2+10x+25$

2. anonymous

$x^2+x-42=0$ now factor $(x+7)(x-6)=0$ so we get $x=-7$ or $x=6$ and now we have to check the answers because we squared.

3. anonymous

$\sqrt{9\times 6+67}=6+5$ $\sqrt{54+67}=11$ $\sqrt{121}=11$ checks

4. anonymous

-7 doesn't work because the left hand side $-7+5=-2$ is negative and the square root of anything is positive

5. anonymous