(8x-6)(5x+1)=0

Solution for (8x-6)(5x+1)=0 equation:

(8x-6)(5x+1)=0

We multiply parentheses ..

(+40x^2+8x-30x-6)=0

We get rid of parentheses

40x^2+8x-30x-6=0

We add all the numbers together, and all the variables

40x^2-22x-6=0

a = 40; b = -22; c = -6;
Δ = b2-4ac
Δ = -222-4·40·(-6)
Δ = 1444
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1444}=38$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-22)-38}{2*40}=\frac{-16}{80}
=-1/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-22)+38}{2*40}=\frac{60}{80}
=3/4
$