Question 707329
Square both sides and simplify.  You may make to:
{{{x+16=2*sqrt(3x+12)}}}


Square both sides again and simplify, getting:
{{{x^2+20x+208=0}}}


Easiest to use formula for solution to quadratic equation:
{{{x=(-20+sqrt(20^2-4*208))/2}}}
OR
{{{x=(-20-sqrt(20^2-4*208))/2}}}
and find what you get.


You get -10+6i or -10-6i  
(complex results)