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=1 b=3 c=−10 , then
D = b^2 - 4 * a * c =
(3)^2 - 4 * (1) * (-10) = 49
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or x1=2 x2=−5
Vieta's Theorem
it is reduced quadratic equation px+q+x2=0 where p=ab p=3 q=ac q=−10 Vieta Formulas x1+x2=−p x1x2=q x1+x2=−3 x1x2=−10