w(w+3)-320=0

Solution for w(w+3)-320=0 equation:

w(w+3)-320=0

We multiply parentheses

w^2+3w-320=0

a = 1; b = 3; c = -320;
Δ = b2-4ac
Δ = 32-4·1·(-320)
Δ = 1289
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-\sqrt{1289}}{2*1}=\frac{-3-\sqrt{1289}}{2}
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+\sqrt{1289}}{2*1}=\frac{-3+\sqrt{1289}}{2}
$