1.9969y^2-y-0.9878=0

Solution for 1.9969y^2-y-0.9878=0 equation:

1.9969y^2-y-0.9878=0

We add all the numbers together, and all the variables

1.9969y^2-1y-0.9878=0

a = 1.9969; b = -1; c = -0.9878;
Δ = b2-4ac
Δ = -12-4·1.9969·(-0.9878)
Δ = 8.89015128
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-\sqrt{8.89015128}}{2*1.9969}=\frac{1-\sqrt{8.89015128}}{3.9938}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{8.89015128}}{2*1.9969}=\frac{1+\sqrt{8.89015128}}{3.9938}
$