4v^2+11v=20

Solution for 4v^2+11v=20 equation:

4v^2+11v=20

We move all terms to the left:

4v^2+11v-(20)=0

a = 4; b = 11; c = -20;
Δ = b2-4ac
Δ = 112-4·4·(-20)
Δ = 441
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{441}=21$
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(11)-21}{2*4}=\frac{-32}{8}
=-4
$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(11)+21}{2*4}=\frac{10}{8}
=1+1/4
$