7. which of the following relations is a function? a.{(2, 3), (-2, 3), (3, 2), (-3,-2)} b.{(8,-4), (-4, 8), (-4, -8), (-8,4)} c.{(9, -1), (-1, 9), (9, 2), (2, -1)} d.{(5, -7), (4, 6), (-3, 8), (5,9)}

A function means that each x can only have one y-value

B, C, and D are NOT functions because they have x-values that have multiple y-values.

For example

B. has two values for -4:

(-4, 8) and (-4, -8)

C. has two values for 9:

(9, -1) and (9, 2)

D. has two values for 5:

(5, -7) and (5, 9)

This makes A. the only function

Hope this helped!

~Just a girl in love with Shawn Mendes

you probably already have the answer but anyways it's b. 15.0

step-by-step explanation: