I really don't understand this problem (how to do it) at all, could someone please show and explain it to me?

Given vectors u=-5i + 9j and v=4i+9j
Find 2u-10v in terms of unit vectors i & j.

(Sorry I can't make the vector signals)

Question

I really don't understand this problem (how to do it) at all, could someone please show and explain it to me? 

Given vectors u=-5i + 9j  and  v=4i+9j
Find 2u-10v in terms of unit vectors i & j. 

(Sorry I can't make the vector signals)

anonymous · Answer

So...2u=-10i+18j and -10v=-40i-90j.
2u-10v=-10i+18j-40i-90j=-50i-62j.
That's it i guess.

anonymous · Answer

You have to separately calculate the i and the j on the both: x axis and y axis.

anonymous · Answer

The answers are in multiple choice
A.  -71i - 51j
B.  -50i - 72j
C.  -77i - 51j
D.  -47i - 51j

I don't know how to do that.

anonymous · Answer

ummm...yeah...my fault...90-18=72...not 62.
So it's B.

anonymous · Answer

Alright, thank you very much.