(5x-5)(4x+6)=0

Solution for (5x-5)(4x+6)=0 equation:

(5x-5)(4x+6)=0

We multiply parentheses ..

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

We get rid of parentheses

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

We add all the numbers together, and all the variables

20x^2+10x-30=0

a = 20; b = 10; c = -30;
Δ = b2-4ac
Δ = 102-4·20·(-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{-(10)-50}{2*20}=\frac{-60}{40}
=-1+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+50}{2*20}=\frac{40}{40}
=1
$