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Quadrilateral Vector question

greenmartian · 2009-09-19 14:20:52

Hi everyone, there is no diagram with this question but it states as follows; In a quadrilateral ABCD, →AB = a →BC = b →CD = c Find →DA The answer is provided as -a -b -c I can see how the answer provided is correct, though would it not also be correct and simpler to state that the answer is -b Thanks!

19-09-2009 2:20pm

#1

greenmartian

Closed Accounts Posts: 2 ✭

Join Date: September 2009

Posts: 1

Hi everyone,

there is no diagram with this question but it states as follows;

In a quadrilateral ABCD,
→AB = a
→BC = b
→CD = c

Find →DA

The answer is provided as -a -b -c

I can see how the answer provided is correct, though would it not also be correct and simpler to state that the answer is -b

Thanks!

0

Comments

#2 19-09-2009 2:50pm

Michael Collins

Moderators, Science, Health & Environment Moderators Posts: 1,852 Mod ✭✭✭✭

Join Date: July 2001

Posts: 1736

Maybe you're getting confused between a quadrilateral and a parallelogram. In a quadrilateral the sides arn't necessarily parallel, it's just a shape with 4 sides, so -b could well be a different length and direction to -a -b -c.

0
#3 19-09-2009 3:33pm

greenmartian

Closed Accounts Posts: 2 ✭

Join Date: September 2009

Posts: 1

Yes, that's what I was doing wrong. Thank you

0