(v+2)(v-1)=54

Solution for (v+2)(v-1)=54 equation:

(v+2)(v-1)=54

We move all terms to the left:

(v+2)(v-1)-(54)=0

We multiply parentheses ..

(+v^2-1v+2v-2)-54=0

We get rid of parentheses

v^2-1v+2v-2-54=0

We add all the numbers together, and all the variables

v^2+v-56=0

a = 1; b = 1; c = -56;
Δ = b2-4ac
Δ = 12-4·1·(-56)
Δ = 225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{225}=15$
$v_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-15}{2*1}=\frac{-16}{2}
=-8
$
$v_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+15}{2*1}=\frac{14}{2}
=7
$