Question

U = (-7, -1), V = (5, -14)..Is it a orthogonal, parallel, or neither? I'm not sure how to find out which one it is..

Answer 1

parallel means that one of the vectors is a scalar multiple of the other

ortho means that the product of their slopes = -1, or dot product is zero

Answer 2

if neither condition is true, then it neither of them ....

Answer 3

so would i use this fromula: U1 V1 + U2 V2?

Answer 4

that would be dot product yes

Answer 5

i got -21 so its parallel?

Answer 6

can you produce one vector by scaling the other?

Answer 7

I don't know what that means..Could you give me an example?

Answer 8

if s<a,b> = <n,m> then <a,b> is // to <n,m>

Answer 9

i gotta a sensitive touch pad :)

if <-7,-1> is parallel to <5,-14>, then there would be some number "s" such that

s<-7,-1> = <5,-14>

<-7s,-s> = <5,-14>

-7s = 5 and -s = -14

is there a scalar "s" that makes this condition true?

Answer 10

So its not parallel..? Sorry I'm so confused! My teacher never went over this in class, I have no notes on this

Answer 11

what are parallel lines?

Answer 12

-7s = 5 and -s = -14
s = 5/-7 s = -14.-1

notice that this is just a ratio of the vector parts; if the ratio of the parts are equal, they are parallel

-7,-1
------ ; since -7/5 is not equal to 1/14; they are not parallel
5,-14

Answer 13

So it must be neither since the dot product is not equal to zero?

Answer 14

It is neither. one way to get a feeling for the problem is sketch the vectors
they start at 0,0



They do not look parallel. they might be perpendicular, so do the dot product test
if you do not get 0, they are not perpendicular (they are not, btw)