X^2-8x-9x=5

Solution for X^2-8x-9x=5 equation:

X^2-8X-9X=5

We move all terms to the left:

X^2-8X-9X-(5)=0

We add all the numbers together, and all the variables

X^2-17X-5=0

a = 1; b = -17; c = -5;
Δ = b2-4ac
Δ = -172-4·1·(-5)
Δ = 309
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{309}}{2*1}=\frac{17-\sqrt{309}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-17)+\sqrt{309}}{2*1}=\frac{17+\sqrt{309}}{2}
$