Question

Which of the following sets of ordered pairs do NOT belong to one-to-one functions? Select all that apply.

Select all that apply:

{(1,−4),(5,−3),(−4,3),(1,−2)}

{(2,5),(−1,7),(5,−9),(3,2)}

{(−4,6),(−2,3),(1,7),(11,10)}

{(2,−1),(7,4),(5,−1),(−1,3)}

Answer 1

@AZ

Answer 2

remember what we said about the y-values being the same if it's not a one-to-one function?

Answer 3

yep

Answer 4

so if they do not belong to one-to-one functions then they should have points with the same y-values

Answer 5

they all have different y values

Answer 6

except d

Answer 7

okay, good

that's one correct answer

Answer 8

now look at the x-values, if there's anything repeating there

then it wouldn't even be a function

Answer 9

if its not a function can it be one on one

Answer 10

if it's not a function, it CANNOT be one-to-one because

one-to-one are functions that only one y-value for each x-value

Answer 11

A and D?

Answer 12

functions can have the same y-value for multiple x-values

BUT if it's a one-to-one, it has to have different y-values for each x-value

and it's not a function if it has the same x-value for different y-values

Answer 13

so the way you can remember all of that is by the vertical and horizontal line test

Answer 14

a and d?

Answer 15

yes, that's correct