-16x^2+21x+106=0

Solution for -16x^2+21x+106=0 equation:

-16x^2+21x+106=0

a = -16; b = 21; c = +106;
Δ = b2-4ac
Δ = 212-4·(-16)·106
Δ = 7225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{7225}=85$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(21)-85}{2*-16}=\frac{-106}{-32}
=3+5/16
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(21)+85}{2*-16}=\frac{64}{-32}
=-2
$