9.81x^2-13.9466x-5.7975=0

Solution for 9.81x^2-13.9466x-5.7975=0 equation:

9.81x^2-13.9466x-5.7975=0

a = 9.81; b = -13.9466; c = -5.7975;
Δ = b2-4ac
Δ = -13.94662-4·9.81·(-5.7975)
Δ = 422.00155156
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{-(-13.9466)-\sqrt{422.00155156}}{2*9.81}=\frac{13.9466-\sqrt{422.00155156}}{19.62}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-13.9466)+\sqrt{422.00155156}}{2*9.81}=\frac{13.9466+\sqrt{422.00155156}}{19.62}
$