Question 121397
3 + {{{sqrt(x^2-8x)}}} =0 --> subtract 3 from both sides
{{{sqrt(x^2-8x)}}} = -3 --> square both sides
x^2-8x = 9 --> subtract 9 from both sides
x^2-8x-9 = 0 ---> factor
(x+1)(x-9) = 0 ---> set each factor equal to 0 and solve <br>

x = -1 and x = 9