I don't understand them please some one help me!!!!ASAP!!!

Answer 1

http://www.mathsisfun.com/sets/function.html

Answer 2

help me too

Answer 3

Okay take this problem for example :
x 8x y
0 8(0) 0
1 8(1) 8
2 8(2) 16
3 8(3) 24
You multiply the numbers in parenthesis
by 8.