(v+2)(5v+8)=0

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

(v+2)(5v+8)=0

We multiply parentheses ..

(+5v^2+8v+10v+16)=0

We get rid of parentheses

5v^2+8v+10v+16=0

We add all the numbers together, and all the variables

5v^2+18v+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:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

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