(4x-9)(3x+11)=0

Solution for (4x-9)(3x+11)=0 equation:

(4x-9)(3x+11)=0

We multiply parentheses ..

(+12x^2+44x-27x-99)=0

We get rid of parentheses

12x^2+44x-27x-99=0

We add all the numbers together, and all the variables

12x^2+17x-99=0

a = 12; b = 17; c = -99;
Δ = b2-4ac
Δ = 172-4·12·(-99)
Δ = 5041
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5041}=71$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(17)-71}{2*12}=\frac{-88}{24}
=-3+2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+71}{2*12}=\frac{54}{24}
=2+1/4
$