5(y-8)(-y+2)=0

Solution for 5(y-8)(-y+2)=0 equation:

5(y-8)(-y+2)=0

We add all the numbers together, and all the variables

5(y-8)(-1y+2)=0

We multiply parentheses ..

5(-1y^2+2y+8y-16)=0

We multiply parentheses

-5y^2+10y+40y-80=0

We add all the numbers together, and all the variables

-5y^2+50y-80=0

a = -5; b = 50; c = -80;
Δ = b2-4ac
Δ = 502-4·(-5)·(-80)
Δ = 900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{900}=30$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(50)-30}{2*-5}=\frac{-80}{-10}
=+8
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(50)+30}{2*-5}=\frac{-20}{-10}
=+2
$