Write 5.3421 (bar on 21) in p/q form

Is the following relation a function? x y 1 4 −1 −2 3 10 5 16 yes no

Adrawer contains 12 identical white socks, 18 identical black socks and 14 identical brown socks. what is the least number of socks you must choose, without looking, to be certain that you have chosen two socks of the same colour?

W-16=-12 solve each one step equation plz