-5x^2+150x+2000=0

Solution for -5x^2+150x+2000=0 equation:

-5x^2+150x+2000=0

a = -5; b = 150; c = +2000;
Δ = b2-4ac
Δ = 1502-4·(-5)·2000
Δ = 62500
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{62500}=250$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(150)-250}{2*-5}=\frac{-400}{-10}
=+40
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(150)+250}{2*-5}=\frac{100}{-10}
=-10
$