-10x^2+100x+12000=0

Solution for -10x^2+100x+12000=0 equation:

-10x^2+100x+12000=0

a = -10; b = 100; c = +12000;
Δ = b2-4ac
Δ = 1002-4·(-10)·12000
Δ = 490000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{490000}=700$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(100)-700}{2*-10}=\frac{-800}{-20}
=+40
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(100)+700}{2*-10}=\frac{600}{-20}
=-30
$