(v-2)(9v+5)=0

Solution for (v-2)(9v+5)=0 equation:

(v-2)(9v+5)=0

We multiply parentheses ..

(+9v^2+5v-18v-10)=0

We get rid of parentheses

9v^2+5v-18v-10=0

We add all the numbers together, and all the variables

9v^2-13v-10=0

a = 9; b = -13; c = -10;
Δ = b2-4ac
Δ = -132-4·9·(-10)
Δ = 529
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{529}=23$
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-13)-23}{2*9}=\frac{-10}{18}
=-5/9
$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-13)+23}{2*9}=\frac{36}{18}
=2
$