-x^2+39x-200=0

Solution for -x^2+39x-200=0 equation:

-x^2+39x-200=0

We add all the numbers together, and all the variables

-1x^2+39x-200=0

a = -1; b = 39; c = -200;
Δ = b2-4ac
Δ = 392-4·(-1)·(-200)
Δ = 721
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(39)-\sqrt{721}}{2*-1}=\frac{-39-\sqrt{721}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(39)+\sqrt{721}}{2*-1}=\frac{-39+\sqrt{721}}{-2}
$