10x^2-17x-90=0

Solution for 10x^2-17x-90=0 equation:

10x^2-17x-90=0

a = 10; b = -17; c = -90;
Δ = b2-4ac
Δ = -172-4·10·(-90)
Δ = 3889
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{3889}}{2*10}=\frac{17-\sqrt{3889}}{20}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-17)+\sqrt{3889}}{2*10}=\frac{17+\sqrt{3889}}{20}
$