Question

Which relation is a function?

A. (0, –45), (–45, –13), (18, –45)

B. (33, –11), (23, 18), (23, –9)

C. (8, 48), (8, 55), (9, 60)

D. (–13, 30), (30, 19), (–13, 39)

Answer 1

A, same reason as last time

Answer 2

Remember, a certain "x" value can only be used once in a set of points. For A, the "x" values are 0, -45, and 18, so they are all different and pass the Vertical Line Test.

Answer 3

How to know if its a function, you have lets say three points (x1,y1) (x2,y2) (x3,y3) as long that none of the x values are repeated then it is a function like if it is (1,1) (1,2) then it is not a function because the X which is 1 is used twice.....however if the y is used more than once its still a function so A is the correct answer

Answer 4

Its A hun :)

Answer 5

an x value can be repeated so long as it always has the same y value. A function is a relationship where each value of x is uniquely associated with a value of y.

This is a function: (1,1), (1,1), (2,1), (3,1)
each value of x has a unique value of y. If you see x = 1, you know y = 1.

This is not a function: (1,1), (1,2), (2,1), (3,1)
If you see x = 1, you don't know if y = 1 or y = 2. Not a unique association.

Answer 6

Some people will incorrectly tell you that if the x value is repeated in the list, it is not a function. A repeat of an x value is not a deal-breaker — only if there are multiple values of y associated with the same value of x is the relationship not a function.