x^2-36x-18=0

Solution for x^2-36x-18=0 equation:

x^2-36x-18=0

a = 1; b = -36; c = -18;
Δ = b2-4ac
Δ = -362-4·1·(-18)
Δ = 1368
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:

$\sqrt{\Delta}=\sqrt{1368}=\sqrt{36*38}=\sqrt{36}*\sqrt{38}=6\sqrt{38}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-36)-6\sqrt{38}}{2*1}=\frac{36-6\sqrt{38}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-36)+6\sqrt{38}}{2*1}=\frac{36+6\sqrt{38}}{2}
$