using the quadratic formula solve the equation 9x2+7x-2=0 - Maths - Quadratic Equations

Question

using the quadratic formula solve the equation
9x2+7x-2=0

Varun.Rawat · Accepted Answer

$9 x^{2} + 7 x - 2 = 0$

Comparing the above quadratic equation with ax²+ bx + c = 0, we get

a = 9 ; b = 7 ; c = -2

D = b²- 4ac = (7)²- 4 (9) (-2) = 49 + 72 = 121 > 0

So the given equation has real and distinct roots which are given by :

$x = \frac{- b + \sqrt{D}}{2 a} a n d x = \frac{- b - \sqrt{D}}{2 a} x = \frac{- 7 + 11}{18} a n d x = \frac{- 7 - 11}{18} x = 2 / 9 a n d x = - 1$