-36=w(w+15)

Solution for -36=w(w+15) equation:

-36=w(w+15)

We move all terms to the left:

-36-(w(w+15))=0


We calculate terms in parentheses: -(w(w+15)), so:

w(w+15)

We multiply parentheses

w^2+15w

Back to the equation:

-(w^2+15w)


We get rid of parentheses

-w^2-15w-36=0

We add all the numbers together, and all the variables

-1w^2-15w-36=0

a = -1; b = -15; c = -36;
Δ = b2-4ac
Δ = -152-4·(-1)·(-36)
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-15)-9}{2*-1}=\frac{6}{-2}
=-3
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-15)+9}{2*-1}=\frac{24}{-2}
=-12
$