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# i don't get this [simplifying] watch

1. ok so im doing a piece of work and i get to to point of:

now i would simplify it by multiplying the two numbers them multiplying that by the 2nd vector then subtract that from the first vector, but the teacher done this:

\frac{1}{5} \begin{vmatrix} (10 - 4) \\ (5 - 8) \end{vmatrix} = \frac{3}{5} \begin{vmatrix} 2 \\ -1 \end{vmatrix}[/latex]

i got the same answer, but i don't get his working out. what did he do. someone please explain what he did please. thanks
2. (Original post by Prokaryotic_crap)
ok so im doing a piece of work and i get to to point of:

now i would simplify it by multiplying the two numbers them multiplying that by the 2nd vector then subtract that from the first vector, but the teacher done this:

i got the same answer, but i don't get his working our. what did he do. someone please explain what he did please. thanks
He wrote the first vector as 1/5*5*(2, 1)= 1/5*(10, 5), and the second as 1/5*4*(1, 2)=1/5*(4, 8), then subtracted the two.
3. (Original post by Tempeststurm)
He wrote the first vector as 1/5*5*(2, 1)= 1/5*(10, 5), and the second as 1/5*4*(1, 2)=1/5*(4, 8), then subtracted the two.
oh i see, yes.

thanks

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