X*x-5.5x-3=0

Solution for X*x-5.5x-3=0 equation:

X*X-5.5X-3=0

We add all the numbers together, and all the variables

-5.5X+X*X-3=0

Wy multiply elements

X^2-5.5X-3=0

a = 1; b = -5.5; c = -3;
Δ = b2-4ac
Δ = -5.52-4·1·(-3)
Δ = 42.25
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{-(-5.5)-\sqrt{42.25}}{2*1}=\frac{5.5-\sqrt{42.25}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5.5)+\sqrt{42.25}}{2*1}=\frac{5.5+\sqrt{42.25}}{2}
$