I can't say i did the problem but from a general format. 0 </= x </= 5 are what is called and interval [0 to 5] those are your x values, your function is of course the y=-x+3 plug in the x values, which will give you the y. graph it, using the x and corresponding y. do the same for the 2nd portion. and you already know your domain (x) as b already tells you. 0,1,2,3,4,5..
