Question

I am bit of confused from this question. I have shown the work below and to subtract, am I supposed to be X2 - X1, Y2-Y1, Z2-Z1? or X1-X2, Y1-Y2, Z1-Z2?
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A triangle has sides formed by the vectors PA=(2,7,3) and PB=(6,2,2). The point P=(1,3,2). Determine the coordinates of the vertices.

Here is what I have done.

PA-P=(2,7,3)-(1,3,2)
=(-1,-4,-1)

PB-P=(6,2,2) - (1,3,2)
=(-5,1,0)

Answer 1

We used to write vectors with [ ] brackets to avoid confusion with points

let point A be (a,b,c), point P is (1,3,2)
then vector PA = [a-1 , b-3 , c-2) = [2 , 7 , 3]
a-1 = 2 ---> a = 3
b-3 = 7 ---> b = 10
c-2 = 3 ---> c = 5

check: for A(3,10,5) and P(1,3,2)
vector PA = [2,7,3]

do the other in the same way

Answer 2

Why add?

Answer 3

Where do you see me adding.

in
vector PA = [a-1 , b-3 , c-2} = [2 , 7 , 3]
I even showed my subtraction of the numbers very explicitly.
Furthermore in my check to prove my answer is correct, you can see that I subtracted the values to get the original vector [2,7,3]

Answer 4

Sorry for the confusion. May I ask why my answer does not work? :S its asking for the vertices, not equal to Point P.