-5x^2+100x+12000=0

Solution for -5x^2+100x+12000=0 equation:

-5x^2+100x+12000=0

a = -5; b = 100; c = +12000;
Δ = b2-4ac
Δ = 1002-4·(-5)·12000
Δ = 250000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{250000}=500$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(100)-500}{2*-5}=\frac{-600}{-10}
=+60
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(100)+500}{2*-5}=\frac{400}{-10}
=-40
$