(2x+8)(3x-5)=0

Solution for (2x+8)(3x-5)=0 equation:

(2x+8)(3x-5)=0

We multiply parentheses ..

(+6x^2-10x+24x-40)=0

We get rid of parentheses

6x^2-10x+24x-40=0

We add all the numbers together, and all the variables

6x^2+14x-40=0

a = 6; b = 14; c = -40;
Δ = b2-4ac
Δ = 142-4·6·(-40)
Δ = 1156
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1156}=34$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-34}{2*6}=\frac{-48}{12}
=-4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+34}{2*6}=\frac{20}{12}
=1+2/3
$