10x^2-9x-91=0

Solution for 10x^2-9x-91=0 equation:

10x^2-9x-91=0

a = 10; b = -9; c = -91;
Δ = b2-4ac
Δ = -92-4·10·(-91)
Δ = 3721
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3721}=61$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-9)-61}{2*10}=\frac{-52}{20}
=-2+3/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-9)+61}{2*10}=\frac{70}{20}
=3+1/2
$