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Proving two lines are coplanar

(x-2)/3 = (y+1)/-2 = z/-8

(x+1)/1 = y/2, z=7

How would I go about starting this off? Also, the direction vector for the second line is (1, 2, 0), right?

Reply 1

atsruser

Two lines are coplanar if a) they are parallel or b) they intersect i.e. if they are not skew.

Reply 2

user2020user

Original post by TSR561

...

The direction vector for the second line being

\mathbf{i} + 2\mathbf{j}

implies that you can divide by 0. You can't.

The

\mathbf{k}

component for the direction vector of the second line should be equal to 1 so the overall direction vector should be

\mathbf{i} + 2\mathbf{j} + \mathbf{k}

(edited 9 years ago)

Reply 3

brianeverit

Original post by TSR561

(x-2)/3 = (y+1)/-2 = z/-8

(x+1)/1 = y/2, z=7

How would I go about starting this off? Also, the direction vector for the second line is (1, 2, 0), right?