What is the domain of the given function?

{(3, –2), (6, 1), (–1, 4), (5, 9), (–4, 0)}

1.{x | x = –4, –1, 3, 5, 6}
2.{y | y = –2, 0, 1, 4, 9}
3.{x | x = –4, –2, –1, 0, 1, 3, 4, 5, 6, 9}
4.{y | y = –4, –2, –1, 0, 1, 3, 4, 5, 6, 9}

Luke started a weight-loss program. the first week, he lost x pounds. the second week, he lost pounds less than times the pounds he lost the first week. the third week, he lost 1 pound more than of the pounds he lost the first week. liam started a weight-loss program when luke did. the first week, he lost 1 pound less than times the pounds luke lost the first week. the second week, he lost 4 pounds less than times the pounds luke lost the first week. the third week, he lost pound more than times the pounds luke lost the first week.