Question 134333
Solve by completing the square:
{{{x^2-8x+15 = 0}}} Subtract 15 from both sides.
{{{x^2-8x = -15}}} Complete the square in x by adding the square of half the x-coefficient {{{(-8/2)^2 = 16}}} to both sides.
{{{x^2-8x+16 = -15+16}}} Factor the left sides.
{{{(x-4)^2 = 1}}} Take the square root of both sides.
{{{(x-4) = 1}}} or {{{(x-4) = -1}}} so...
{{{x = 4+1}}} or {{{x = 4-1}}}
{{{x = 5}}} or {{{x = 3}}}