Find cartesian equations of the line of intersection of the planes

ezsmith
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Homework Statement


Find cartesian equations of the line of intersection of the planes x+3y-6z =2 and 2x+7y-3z=7

The Attempt at a Solution


What I did first was I cross product the 2 equation and then I got 33i-9j+k
Then I took both of the equation and let y = 0. After that my answer seems to be weird.. Did I did anything wrong? The answer of the book was given ∴x+7/33 = y-3/-9 = z
 
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ezsmith said:

Homework Statement


Find cartesian equations of the line of intersection of the planes x+3y-6z =2 and 2x+7y-3z=7

The Attempt at a Solution


What I did first was I cross product the 2 equation and then I got 33i-9j+k
Then I took both of the equation and let y = 0. After that my answer seems to be weird.. Did I did anything wrong? The answer of the book was given ∴x+7/33 = y-3/-9 = z
What do you mean by weird? In any case, your method, at least to me, seems to be a bit of overkill. Why not just solve the system of equations the usual way?
 
vela said:
What do you mean by weird? In any case, your method, at least to me, seems to be a bit of overkill. Why not just solve the system of equations the usual way?

Never mind. I managed to solve it. Thank you for the reply :)
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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