5x^2-18x-99=0

Solution for 5x^2-18x-99=0 equation:

5x^2-18x-99=0

a = 5; b = -18; c = -99;
Δ = b2-4ac
Δ = -182-4·5·(-99)
Δ = 2304
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2304}=48$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-48}{2*5}=\frac{-30}{10}
=-3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+48}{2*5}=\frac{66}{10}
=6+3/5
$