Answer
$x=4+\sqrt -5,4+\sqrt 5$
Work Step by Step
$3(x-4)^{2}=15$
$(x-4)^{2}=5$
$x-4=\sqrt 5$
$x-4=\sqrt -5$
$x=4+\sqrt -5,4+\sqrt 5$
Divide both sides. Then take the square root of both sides. Then isolate $x$ from both of the resulting equations to get two answers.