-5x^2+60x-100=0

Solution for -5x^2+60x-100=0 equation:

-5x^2+60x-100=0

a = -5; b = 60; c = -100;
Δ = b2-4ac
Δ = 602-4·(-5)·(-100)
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(60)-40}{2*-5}=\frac{-100}{-10}
=+10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(60)+40}{2*-5}=\frac{-20}{-10}
=+2
$