=9x2+12x-4

Solution for =9x2+12x-4 equation:

=9x^2+12x-4

We move all terms to the left:

-(9x^2+12x-4)=0

We get rid of parentheses

-9x^2-12x+4=0

a = -9; b = -12; c = +4;
Δ = b2-4ac
Δ = -122-4·(-9)·4
Δ = 288
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{288}=\sqrt{144*2}=\sqrt{144}*\sqrt{2}=12\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-12\sqrt{2}}{2*-9}=\frac{12-12\sqrt{2}}{-18}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+12\sqrt{2}}{2*-9}=\frac{12+12\sqrt{2}}{-18}
$