Question

Find the ordered pair that represents the vector from B(–6, 2) to C(–12, 7).
A. BC= (1, -10)
B. BC=(-18, 9)
C. BC= (2, -5)
D. BC= (-6, 5)

Find the magnitude of vector WX for W(–3, 5, 4) and X(9, 5, 3).
A. Square Root of 137
B. Square Root of 145
C.140
D. 137

Answer 1

vector BC = c - b = (-12-(-6), 7-2) = (... , ...)

Answer 2

So what do you do? Take -12 - 7 or take both coordinates of b and minus them from all coordinates of c?

Answer 3

-12 - (-6) = -12+6 = ... ?
im not sure u cant calculate of 7-2 = ... ?
then represent as a coordinat, or it can represented as a matrice

Answer 4

I don't know how to do this at all, I'm sorry. Uh, ? I'm supposed to find the ordered pair that represents the vector from B & C. . . you're confusing me even more with the matrices and stuff.

Answer 5

vector WX = <12,0,-1>
its magnitude is sqwr(12^2 +(-1)^2 = sqr (145)

Answer 6

Alright, now that makes sense, thank you.

Answer 7

to find out a vector from 2 points, you take <x2-x1, y2 -y1>, pay attention to the notation < >, it show that is a vector, not a point

Answer 8

and then, from that information, you just take square root of the x ^2 + y^2 (x, y from the vector you 've just found out. by that way, you can find out any vector, and its magnitude no matter what it is in R^2 or R^3
Hope this help

Answer 9

Thank you very much, the both of you. I'm apologize, when it comes to math - it takes a lot to get me to understand what I'm supposed to be doing.