Answer:
2) Yes, each x-coordinate is only used once.
3) {1,2,3,4}
4) {25,45,60,70}
5) (3,60)
6) No because (4,7) and (4,25) share the same x-coordinate.
Explanation:
A relation is a function if there is no more than one y-value assigned to an x.
Any x used can only be used once in an order pair.
You that here.
(1,25)
(2,45)
(3,60)
(4,70)
So basically because all of the x-coordinates are different, this is a function.
The domain is the x-coordinate of each pair (the first of each pair):
{1,2,3,4}.
The range is the y-coordinate of each pair (the second number of each pair):
{25,45,60,70}.
One ordered pair that I see in the table is (3,60). There are 3 others you can choose and I named them above.
{(4,10),(3,15),(1,5),(2,25),(4,25)} is not a function because there are more than one pairs with the same x-coordinate,4.