(3-v)(2v+7)=0

Solution for (3-v)(2v+7)=0 equation:

(3-v)(2v+7)=0

We add all the numbers together, and all the variables

(-1v+3)(2v+7)=0

We multiply parentheses ..

(-2v^2-7v+6v+21)=0

We get rid of parentheses

-2v^2-7v+6v+21=0

We add all the numbers together, and all the variables

-2v^2-1v+21=0

a = -2; b = -1; c = +21;
Δ = b2-4ac
Δ = -12-4·(-2)·21
Δ = 169
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{169}=13$
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-13}{2*-2}=\frac{-12}{-4}
=+3
$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+13}{2*-2}=\frac{14}{-4}
=-3+1/2
$