18v2-15v-18=0

Solution for 18v2-15v-18=0 equation:

18v^2-15v-18=0

a = 18; b = -15; c = -18;
Δ = b2-4ac
Δ = -152-4·18·(-18)
Δ = 1521
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1521}=39$
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-15)-39}{2*18}=\frac{-24}{36}
=-2/3
$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-15)+39}{2*18}=\frac{54}{36}
=1+1/2
$