(-10x-10)(-8x-3)=0

Solution for (-10x-10)(-8x-3)=0 equation:

(-10x-10)(-8x-3)=0

We multiply parentheses ..

(+80x^2+30x+80x+30)=0

We get rid of parentheses

80x^2+30x+80x+30=0

We add all the numbers together, and all the variables

80x^2+110x+30=0

a = 80; b = 110; c = +30;
Δ = b2-4ac
Δ = 1102-4·80·30
Δ = 2500
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2500}=50$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(110)-50}{2*80}=\frac{-160}{160}
=-1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(110)+50}{2*80}=\frac{-60}{160}
=-3/8
$