X^2-4.1x+2.6=0

Solution for X^2-4.1x+2.6=0 equation:

X^2-4.1X+2.6=0

a = 1; b = -4.1; c = +2.6;
Δ = b2-4ac
Δ = -4.12-4·1·2.6
Δ = 6.41
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{-(-4.1)-\sqrt{6.41}}{2*1}=\frac{4.1-\sqrt{6.41}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4.1)+\sqrt{6.41}}{2*1}=\frac{4.1+\sqrt{6.41}}{2}
$