What 2 by 2 matrix P projects the vector (x,y) onto the x axis to produce (x,0)?

What matrix Q projects onto the y axis to produce (0,y)?

If you multiply (5,7) by P and then multiply by Q, you get (_____) and (_____). (Fill in the vector-blanks)

*the vectors in part three arent neccessarily 5 dimensions!)

I'm pretty sure I found P and Q, but for the third problem I only got 1 vector...

My answer:

Q= [

001

100

010]

P= [

010

001

100]

P*Q*(5,7)=(0,0)=0 ... And yet the problem asks for two (i'm assuming nonzero) vectors... What have i done wrong?

(PS Im on my blackberry!)