x=-15x^2+300x+12,000

Solution for x=-15x^2+300x+12,000 equation:

x=-15x^2+300x+12.000

We move all terms to the left:

x-(-15x^2+300x+12.000)=0

We get rid of parentheses

15x^2-300x+x-12.000=0

We add all the numbers together, and all the variables

15x^2-299x-12=0

a = 15; b = -299; c = -12;
Δ = b2-4ac
Δ = -2992-4·15·(-12)
Δ = 90121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-299)-\sqrt{90121}}{2*15}=\frac{299-\sqrt{90121}}{30}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-299)+\sqrt{90121}}{2*15}=\frac{299+\sqrt{90121}}{30}
$