Linear algebra, parametric equation, intersectin of line

cleopatra
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Homework Statement



Two equations for two planes in 3-D
2x+y-2z=1
x-2y+z=-3
Find the parametric equation for the line of intersection of the two planes by solving these two equations togeather.

The Attempt at a Solution



Gauss Jordan gives:
1 0 -3/5 -1/5
0 1 -4/5 7/5

if z=t
x=3/5t-1/5
y=4/5t+7/5

I don´t know how to finish the problem.
 
Last edited:
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You have already solved the problem!

x=3/5t-1/5
y=4/5t+7/5
z=t

is the parametric equation for the intersection.
 
Last edited:
You are already finished. z=t, x=(3/5)t-1/5 and y=(4/5)t+7/5 is the intersection line in parametric form. Are you supposed to express it in vector form or something?
 
really? I thought this was only the parametric equation and I had to find some special line of intersection as well.
 
cleopatra said:
really? I thought this was only the parametric equation and I had to find some special line of intersection as well.

Nah. The problem says find the line that is the intersection of the two planes. No line intersection involved.
 
okey thanks for that
 
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