X^2+x-20.16=0

Solution for X^2+x-20.16=0 equation:

X^2+X-20.16=0

a = 1; b = 1; c = -20.16;
Δ = b2-4ac
Δ = 12-4·1·(-20.16)
Δ = 81.64
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{-(1)-\sqrt{81.64}}{2*1}=\frac{-1-\sqrt{81.64}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{81.64}}{2*1}=\frac{-1+\sqrt{81.64}}{2}
$