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A is the point (98, -17) and B is the point (-39, 39). The vector $\vec {BA}$ has column form given by $\left( \begin {array}{c} h \\ k \end {array}\right)$

What is the value of h?

Cant figure how to resolve this.. do i need to add point A and B after converting them to component form?

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up vote 1 down vote accepted

It looks like you already have them in components. The vector is from $B$ to $A$, so you need to subtract the components, which is subtracting $\vec {OA}- \vec {OB}$.

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is it 137? i minus B-A – JackyBoi Sep 11 '12 at 14:45
OK i am totally confused now i flipped thru my textbook and couldnot find anything, a bit more further explanation will be great. I am totally confused is what are O values? in OA? – JackyBoi Sep 11 '12 at 15:03
A nasty person made up the problem. Note that to find $XY$ we calculate $OY-OX$. So to calculate $BA$ we calculate $OA-OB$. – André Nicolas Sep 11 '12 at 15:24
@JackyBoi: Yes, it is correct, $98-(-39)$. – André Nicolas Sep 11 '12 at 15:27
@JackyBoi: I confused myself, and André Nicolas got it right. I have fixed the answer. – Ross Millikan Sep 11 '12 at 15:33

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