(3+v)(5v+6)=0

Solution for (3+v)(5v+6)=0 equation:

(3+v)(5v+6)=0

We add all the numbers together, and all the variables

(v+3)(5v+6)=0

We multiply parentheses ..

(+5v^2+6v+15v+18)=0

We get rid of parentheses

5v^2+6v+15v+18=0

We add all the numbers together, and all the variables

5v^2+21v+18=0

a = 5; b = 21; c = +18;
Δ = b2-4ac
Δ = 212-4·5·18
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(21)-9}{2*5}=\frac{-30}{10}
=-3
$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(21)+9}{2*5}=\frac{-12}{10}
=-1+1/5
$