8-x2-17x-0=0

Solution for 8-x2-17x-0=0 equation:

8-x2-17x-0=0

We add all the numbers together, and all the variables

-1x^2-17x+8=0

a = -1; b = -17; c = +8;
Δ = b2-4ac
Δ = -172-4·(-1)·8
Δ = 321
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-17)-\sqrt{321}}{2*-1}=\frac{17-\sqrt{321}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-17)+\sqrt{321}}{2*-1}=\frac{17+\sqrt{321}}{-2}
$