Finding equation of the line orthogonal to a plane & the intersection point?

HardlyPuzzled

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Apr 20, 2019
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I'm not sure I'm doing this correctly. If anyone could validate this it would be much appreciated!

1) Consider the line that is orthogonal to the plane 3x-2y+4z=6 and that passes through the point (-1,2,3).

a) Find the equation of this line.

<-1,2,3> + t<3,-2,4>
<-1+3t, 2-2t, 3+4t>

x= -1+3t
y= 2-2t
z= 3+4t

b) Determine where the line intersects the plane.

3(-1+3t) - 2(2-2t) + 4(3+4t) = 6
-3+9t-4+4t+12+16t = 6
29t = 1
t = 1/29

Plugging t into x,y, and z:

(-26/29, 56/29, 91/29)
 
Looks good to me, and it's easy enough to check.

What part were you unsure of?
 
Looks good to me, and it's easy enough to check.

What part were you unsure of?

I guess I was just a little confused on the wording of the question. So basically when you're asked for the equation of a line in R3, it's the same as asking for the parametric equations?
 
I guess I was just a little confused on the wording of the question. So basically when you're asked for the equation of a line in R3, it's the same as asking for the parametric equations?
No that is not necessarily true.
Now I do prefer the parametric form of the line. But the symmetric and vector forms are widely used.
Symmetric: \(\displaystyle \frac{x+1}{3}=\frac{y-2}{-2}=\frac{z-3}{4}\)
Vector: \(\displaystyle \ell: \left<-1+3t,~ 2-2t,~ 3+4t\right>\)
Are all useful and correct.
 
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