-2.5x^2+100x-360=0

Solution for -2.5x^2+100x-360=0 equation:

-2.5x^2+100x-360=0

a = -2.5; b = 100; c = -360;
Δ = b2-4ac
Δ = 1002-4·(-2.5)·(-360)
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(100)-80}{2*-2.5}=\frac{-180}{-5}
=+36
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(100)+80}{2*-2.5}=\frac{-20}{-5}
=+4
$