5-11x-16x^2=0

Solution for 5-11x-16x^2=0 equation:

5-11x-16x^2=0

a = -16; b = -11; c = +5;
Δ = b2-4ac
Δ = -112-4·(-16)·5
Δ = 441
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{441}=21$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-11)-21}{2*-16}=\frac{-10}{-32}
=5/16
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-11)+21}{2*-16}=\frac{32}{-32}
=-1
$