(w+5)(3w)=336

Solution for (w+5)(3w)=336 equation:

(w+5)(3w)=336

We move all terms to the left:

(w+5)(3w)-(336)=0

We multiply parentheses

3w^2+15w-336=0

a = 3; b = 15; c = -336;
Δ = b2-4ac
Δ = 152-4·3·(-336)
Δ = 4257
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{4257}=\sqrt{9*473}=\sqrt{9}*\sqrt{473}=3\sqrt{473}$
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-3\sqrt{473}}{2*3}=\frac{-15-3\sqrt{473}}{6}
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+3\sqrt{473}}{2*3}=\frac{-15+3\sqrt{473}}{6}
$