Question 389612
Use the quadratic formula {{{x = (-b+-sqrt(b^2-4ac))/2a}}} to solve:
1) {{{0 = x^2+x-20}}} Here, a = 1, b = 1, and c = -20,  make the appropriate substitutions to get:
{{{x = (-1+-sqrt(1^2-4(1)(-20)))/2(1)}}} Evaluate.
{{{x = (-1+-sqrt(1-(-80)))/2}}}
{{{x = (-1/2)+-sqrt(81)/2}}}
{{{x = (-1/2)+(9/2)}}} or {{{x = (-1/2)-(9/2)}}}
{{{x = 4}}} or {{{x = -5}}} 
Use the same approach on the second equation.