Answer
The solutions are -4 and 4.
Work Step by Step
$x^{2}$=16
$x^{2}$-16=16-16
$x^{2}$-16=0
$x^{2}$-$4^{2}$=0
(x+4)(x-4)=0
x+4=0 or x-4=0
x+4-4=0-4 or x-4+4=0+4
x=-4 or x=4
The solutions are -4 and 4.
Check
Let x=-4
$x^{2}$=16
$(-4)^{2}$ =16
16=16
Let x=4
$x^{2}$=16
$4^{2}$ =16
16=16
0=0