1. yes because for every y has a different x
2. no because x (domain) has multiple outputs
3. yes no x value is repeated
4. yes no x value is repeated
5. yes because no x value is repeated
6. yes because there is no x value is repeated
it's really easy, basically for the x values there cannot be the same number
example=
function: (5,6) (6,7)
not a function: (5,6) (5,7) the 5 i used twice
hope this helps ! :)
