-0.05(x-2)(x-18)=0

Solution for -0.05(x-2)(x-18)=0 equation:

-0.05(x-2)(x-18)=0

We multiply parentheses ..

-0.05(+x^2-18x-2x+36)=0

We multiply parentheses

-0.05x^2+0.9x+0.1x-1.8=0

We add all the numbers together, and all the variables

-0.05x^2+x-1.8=0

a = -0.05; b = 1; c = -1.8;
Δ = b2-4ac
Δ = 12-4·(-0.05)·(-1.8)
Δ = 0.64
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{0.64}}{2*-0.05}=\frac{-1-\sqrt{0.64}}{-0.1}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{0.64}}{2*-0.05}=\frac{-1+\sqrt{0.64}}{-0.1}
$