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Equation form of a line in 3-D

  • Thread starter yvonnars
  • Start date
  • #1
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Homework Statement



Fine the equation form of the line L that is perpendicular to the plane Q with equation
-x+3y+2z=1 and passing through the origin.

Homework Equations



Parametric form of a line:
L=(0,0,0)+s(-1,3,2)
so x/-1=y/3=z/2

The Attempt at a Solution


x+y+z=4s
but then what is the value of s?
 

Answers and Replies

  • #2
rock.freak667
Homework Helper
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s is just a parameter, for different values of s you will get different points on the line.

Remember L is also (x,y,z) so get s in terms of each x,y and z and they will all be equal to one another.
 
  • #3
8
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s is just a parameter, for different values of s you will get different points on the line.

Remember L is also (x,y,z) so get s in terms of each x,y and z and they will all be equal to one another.
So will the equation form of this line just be x+y+z=4s?
 
  • #4
rock.freak667
Homework Helper
6,230
31
So will the equation form of this line just be x+y+z=4s?
No, from L=(0,0,0)+s(-1,3,2) = (0-s,0+3s,0+2s)

L = (x,y,z) = (0-s,0+3s,0+2s)

x = 0-s and so on. Just make s the subject for each one and then put them all equal to each other.
 

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