Question

3x²+4x-9=0 then roots are​

Answer 1

$\sf 3x²+4x-9=0$

Value of discriminant,

$\sf D=b²-4ac$

$\sf D=(-4)²-4(3)(-9)$

$\sf D=16+108$

$\sf D=124$

By Quadratic formula,

$\sf x= \frac{-b±√b²-4ac}{2a}$

$\sf x= \frac{-4±√124}{2(3)}$

$\sf x= \frac{-4±2√31}{6}$

$\sf x= \frac{-4}{6}±\frac{2√31}{6}$

$\sf x= \frac{-2±√31}{3}$

$\sf x= \frac{2±√31}{3}$

$\sf x= \frac{2+√31}{3} \:\: or \:\: x=\frac{2-√31}{3}$

$\sf\red{ x= \frac{2+√31}{3} \:\: or \:\: x= \frac{2-√31}{2} }$