I'm doing some multi-variable calculus review, and I had a question (my understanding of the class was not as good as I would have liked it to be).(adsbygoogle = window.adsbygoogle || []).push({});

<b> 1. The problem statement, all variables and given/known data </b>.

Find a plane containing the line r(t) = <6,-6,4> + t<-2,7,-4> and orthogonal to the plane -7x+8y+5z=1.

<b> 2. Relevant equations </b>.

I think I need to use a cross product. I cross <-2,7,-4> and <-7,8,5> to get a vector orthogonal to to the plane (and the line). Then, I use n (dot) (r-r_0), but I keep getting the wrong answer. I fear that my approach is wrong though.

answer is: 635/2

<b> 3. The attempt at a solution </b>.

So when I cross <-2,7,-4> and <-7,8,5> I get <67, 38, 33>, and my plane is 67x+38y+33z=46.

Help please.

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# Homework Help: 3-D Vector question

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