Y=103x2+99.99x-20.86

Solution for Y=103x2+99.99x-20.86 equation:

=103Y^2+99.99Y-20.86

We move all terms to the left:

-(103Y^2+99.99Y-20.86)=0

We get rid of parentheses

-103Y^2-99.99Y+20.86=0

a = -103; b = -99.99; c = +20.86;
Δ = b2-4ac
Δ = -99.992-4·(-103)·20.86
Δ = 18592.3201
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{-(-99.99)-\sqrt{18592.3201}}{2*-103}=\frac{99.99-\sqrt{18592.3201}}{-206}
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-99.99)+\sqrt{18592.3201}}{2*-103}=\frac{99.99+\sqrt{18592.3201}}{-206}
$