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alakd

Guest

algebra (equation of line and plane ) help plzzzzzzzz

Can someone help with this multi-part question. i did the first three but it doesnt seem right!
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(a) Find the equation of the line l through P(1, 1, 2) and Q(1, 0, 4) in vector, parametric and Cartesian forms.
(b) Find the vector form of the line k through R(0, 3, 1) which is perpendicular to l.
(c) Find the Cartesian form of the plane containing the lines l and k.
(d) Find the vector form of the line through T(0, 0, 3) which is normal to this plane.
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so i guess i did the first bit alright : cartesian : z=6+4x , y=6
for the second one i got this line : (-5,4,2)+t(28,-37,7) , i timed it by 17 to get rid of the denominator
third part : the lines seem to have no intersection so i am stuck!

appreciate it if anyone can help out

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: algebra (equation of line and plane ) help plzzzzzzzz

How did you do part one? Your answer doesn't seem to be correct.

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Bob

Administrator

Registered: 2010-06-20

Posts: 10,583

Re: algebra (equation of line and plane ) help plzzzzzzzz

Question:  (a) Find the equation of the line l through P(1, 1, 2) and Q(1, 0, 4) in vector, parametric and Cartesian forms.

Your answer cartesian : z=6+4x , y=6

??

Substitute x = 1 y = 1 and z = 2 into your answer.

Doesn't fit.  So this isn't the asnwer to Q1.  It would have to be y = 1 not 6 for a start.

How are you doing these?

You could have a look at

http://www.mathisfunforum.com/viewtopic … 57#p159557

especially posts  3 and 11.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob