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

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

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

We add all the numbers together, and all the variables

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

We multiply parentheses ..

(+5y^2+40y+8y+64)=0

We get rid of parentheses

5y^2+40y+8y+64=0

We add all the numbers together, and all the variables

5y^2+48y+64=0

a = 5; b = 48; c = +64;
Δ = b2-4ac
Δ = 482-4·5·64
Δ = 1024
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1024}=32$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(48)-32}{2*5}=\frac{-80}{10}
=-8
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(48)+32}{2*5}=\frac{-16}{10}
=-1+3/5
$