Proving Parallelism of Line and Plane in 2x-y+4z=81 and x-2/3=y-3/2=z-1

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SUMMARY

The discussion centers on proving the parallelism of the plane defined by the equation 2x - y + 4z = 81 and the line represented by the parametric equations (x-2)/3 = (y-3)/2 = z-1. The user initially calculated the direction vector of the line as 3i + 2j + k and the normal vector of the plane as 2i - j + 4k. The conclusion drawn is that the line and the plane are not parallel, as their direction and normal vectors are not perpendicular, indicating that they must intersect instead.

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Homework Statement





show that the plane 2x - y + 4z = 81

never intersects the line

[tex]\frac{x-2}{3}[/tex]=[tex]\frac{y-3}{2}[/tex]=z-1



Homework Equations



??


The Attempt at a Solution



I wanted to show that the line and the plane were parallel. So the unit vector for the line would be 3i + 3j + 1k
RIGHT?
Then I get confused how to show this is parallel to the plane
Planes don't have unit vectors do they ?
The vector normal to the plane i suppose is 2i + -j + 4z

So if the two were parallel a dot b would be = 0
but this doesn't work ... help
 
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I think the unit vector of the line is 3i+2j+k. But that doesn't change anything, the direction vector and the normal vector still aren't perpendicular. That can only mean that the line and the plane must intersect. There is probably a typo in the problem.
 

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