Find the distance of the plane `2x-y-2z-9=0` from the origin.

Explanation

To find the distance of the plane \(2x - y - 2z - 9 = 0\) from the origin, we can use the formula for the distance \(d\) from a point \((x_1, y_1, z_1)\) to a plane given by the equation \(Ax + By + Cz + D = 0\):

\[ d = \frac{|Ax_1 + By_1 + Cz_1 + D|}{\sqrt{A^2 + B^2 + C^2}} \]

### Step-by-step solution:

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