-x2+35x-300=0

Solution for -x2+35x-300=0 equation:

-x2+35x-300=0

We add all the numbers together, and all the variables

-1x^2+35x-300=0

a = -1; b = 35; c = -300;
Δ = b2-4ac
Δ = 352-4·(-1)·(-300)
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(35)-5}{2*-1}=\frac{-40}{-2}
=+20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(35)+5}{2*-1}=\frac{-30}{-2}
=+15
$