(8x-2)(10x+15)=0

Solution for (8x-2)(10x+15)=0 equation:

(8x-2)(10x+15)=0

We multiply parentheses ..

(+80x^2+120x-20x-30)=0

We get rid of parentheses

80x^2+120x-20x-30=0

We add all the numbers together, and all the variables

80x^2+100x-30=0

a = 80; b = 100; c = -30;
Δ = b2-4ac
Δ = 1002-4·80·(-30)
Δ = 19600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{19600}=140$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(100)-140}{2*80}=\frac{-240}{160}
=-1+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(100)+140}{2*80}=\frac{40}{160}
=1/4
$