Question 964556
{{{sqrt(x^2+9x+15)=x+5}}} Square each side.
{{{x^2+9x+15=x^2+10x+25}}}
{{{9x+15=10x+25}}}
{{{15=x+25}}}
{{{-10=x}}}
ANSWER: x=-10
{{{CHECK}}}:
{{{sqrt(x^2+9x+15)=x+5}}} 
{{{sqrt(-10^2+9(-10)+15)=(-10)+5}}} 
{{{sqrt(100-90+15)=-5}}}
{{{sqrt(25)=-5}}}
{{{-5=-5}}}