Solve the equation.

Question

X^2+10x-20=0

Answer 1

x = [ -10 +/- sqrt (100 + 80) ]/2

x = -5 +/- .5 sqrt(180)

x = -5 +/- .5 sqrt ( 9 * 4 * 5)

x = -5 +/- 3 sqrt 5