Question 92221
{{{x^2-80=0}}}

add 87 on both sides:

we get {{{x^2 = 80}}}


take square root on both sides:

{{{x = sqrt(80)}}} or{{{x = -sqrt(80)}}}

simplify each of them:

{{{x = 4sqrt(5)}}} or {{{x = -4sqrt(5)}}}