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

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

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

We add all the numbers together, and all the variables

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

We multiply parentheses ..

(-5y^2+8y+10y-16)=0

We get rid of parentheses

-5y^2+8y+10y-16=0

We add all the numbers together, and all the variables

-5y^2+18y-16=0

a = -5; b = 18; c = -16;
Δ = b2-4ac
Δ = 182-4·(-5)·(-16)
Δ = 4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4}=2$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(18)-2}{2*-5}=\frac{-20}{-10}
=+2
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(18)+2}{2*-5}=\frac{-16}{-10}
=1+3/5
$