x2-18x-208=0

Solution for x2-18x-208=0 equation:

x2-18x-208=0

We add all the numbers together, and all the variables

x^2-18x-208=0

a = 1; b = -18; c = -208;
Δ = b2-4ac
Δ = -182-4·1·(-208)
Δ = 1156
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1156}=34$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-34}{2*1}=\frac{-16}{2}
=-8
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+34}{2*1}=\frac{52}{2}
=26
$