X^2-80x+3.6=0

Solution for X^2-80x+3.6=0 equation:

X^2-80X+3.6=0

a = 1; b = -80; c = +3.6;
Δ = b2-4ac
Δ = -802-4·1·3.6
Δ = 6385.6
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{-(-80)-\sqrt{6385.6}}{2*1}=\frac{80-\sqrt{6385.6}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-80)+\sqrt{6385.6}}{2*1}=\frac{80+\sqrt{6385.6}}{2}
$