Question

determine which set of ordered pairs is a function.

a.{(-1,3),(1,4),(-1,5)}
b. {(5,3),(-6,3),(-2,4)}
c. {(0.5, 1.6),(1, 1.75),(1.5, 2.3), (0.5, 3.6)}
d. {(1,2), (-5,4),(3,6),(-5,2)}

Answer 1

Ok do any of your sets include 2 or more points with the same x but with different y?

Answer 2

For the first one:
Do any of your points have same x but different y?

Answer 3

This is the same as the last question you asked. For a function to be a function, an x value will map to one and *only one* y value.

Answer 4

it would be A right?

Answer 5

Should say for a *relation to be a function...

Answer 6

If you see the same x value repeated in the relation set, and it has a different y value with it, then it is not a function.

Answer 7

A) We have same x but different y so A is not a function
(-1,5)
(-1,3)
See same x but different y

Answer 8

b , c or d :) lol

Answer 9

Yes, so which one of those relations has each x value listed only once?

Answer 10

Each relation set you have to choose from is a set of ordered pairs in the format (x,y)

So x will be the first number in each of the ordered pairs.

Answer 11

c? :D

Answer 12

i have a question when they gave you a chart or something and it says whhich relation is a function? how would you know whats the function

Answer 13

C has these two ordered pairs included in the relation set. (0.5,1.6) and (0.5,3.6) So the x value of 0.5 is used twice but outputs a different y value each time. 1.6 and 3.6. So c is also not a function.

I'm not sure of the format of the chart you are asking about, but assuming it is mapping x values to y values, then the answer to your question is that it is a function when each x value is mapped to one and only one y value.

This all refers back to something called the vertical line test. If you can draw a vertical line anywhere on a graph of the relation and hit two (or more) points, then it is not a function. This is exactly because if the vertical line hits two (or more) points, that can only be because a single x value has been mapped to two (or more) y values

Answer 14

oomg thanks!:)

Answer 15

and the answer is d?

Answer 16

The answer is b. Because d also has an x value that is used twice and gives a different y value each time. (-5,4) and (-5,2)

B is the only choice where each x value appears in the set only once.

Answer 17

thank you' really helped me!

Answer 18

you're welcome

Answer 19

you're welcome