(8x-2)(40x-15)=0

Solution for (8x-2)(40x-15)=0 equation:

(8x-2)(40x-15)=0

We multiply parentheses ..

(+320x^2-120x-80x+30)=0

We get rid of parentheses

320x^2-120x-80x+30=0

We add all the numbers together, and all the variables

320x^2-200x+30=0

a = 320; b = -200; c = +30;
Δ = b2-4ac
Δ = -2002-4·320·30
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-200)-40}{2*320}=\frac{160}{640}
=1/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-200)+40}{2*320}=\frac{240}{640}
=3/8
$