0=-x^2+36x-4

Solution for 0=-x^2+36x-4 equation:

0=-x^2+36x-4

We move all terms to the left:

0-(-x^2+36x-4)=0

We add all the numbers together, and all the variables

-(-x^2+36x-4)=0

We get rid of parentheses

x^2-36x+4=0

a = 1; b = -36; c = +4;
Δ = b2-4ac
Δ = -362-4·1·4
Δ = 1280
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:

$\sqrt{\Delta}=\sqrt{1280}=\sqrt{256*5}=\sqrt{256}*\sqrt{5}=16\sqrt{5}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-36)-16\sqrt{5}}{2*1}=\frac{36-16\sqrt{5}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-36)+16\sqrt{5}}{2*1}=\frac{36+16\sqrt{5}}{2}
$