A quadratic equation can be solved using the discriminant. The roots of the quadratic equation: x1=2aD−b x2=2a−D−b where D = b^2 - 4*a*c - it is the discriminant. Because a=2 b=−8 c=0 , then
D = b^2 - 4 * a * c =
(-8)^2 - 4 * (2) * (0) = 64
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or x1=4 x2=0
Vieta's Theorem
rewrite the equation 2x2−8x=0 of ax2+bx+c=0 as reduced quadratic equation x2+abx+ac=0 x2−4x=0 px+q+x2=0 where p=ab p=−4 q=ac q=0 Vieta Formulas x1+x2=−p x1x2=q x1+x2=4 x1x2=0