-x2+60x-125=0

Solution for -x2+60x-125=0 equation:

-x2+60x-125=0

We add all the numbers together, and all the variables

-1x^2+60x-125=0

a = -1; b = 60; c = -125;
Δ = b2-4ac
Δ = 602-4·(-1)·(-125)
Δ = 3100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{3100}=\sqrt{100*31}=\sqrt{100}*\sqrt{31}=10\sqrt{31}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(60)-10\sqrt{31}}{2*-1}=\frac{-60-10\sqrt{31}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(60)+10\sqrt{31}}{2*-1}=\frac{-60+10\sqrt{31}}{-2}
$