(4y-8)(79+y)=y

Solution for (4y-8)(79+y)=y equation:

(4y-8)(79+y)=y

We move all terms to the left:

(4y-8)(79+y)-(y)=0

We add all the numbers together, and all the variables

(4y-8)(y+79)-y=0

We add all the numbers together, and all the variables

-1y+(4y-8)(y+79)=0

We multiply parentheses ..

(+4y^2+316y-8y-632)-1y=0

We get rid of parentheses

4y^2+316y-8y-1y-632=0

We add all the numbers together, and all the variables

4y^2+307y-632=0

a = 4; b = 307; c = -632;
Δ = b2-4ac
Δ = 3072-4·4·(-632)
Δ = 104361
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(307)-\sqrt{104361}}{2*4}=\frac{-307-\sqrt{104361}}{8}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(307)+\sqrt{104361}}{2*4}=\frac{-307+\sqrt{104361}}{8}
$