Question

which relation is also a function?
a.
image of a coordinate plane with points

b.

x	y
10	1
15	2
15	3
20	4
20	5

c. {(-8,8), (-6,5), (-6,4), (-3,1), (-1,0)}

d. partially visible, likely another relation representation

Explanation:

Step1: Recall function definition

A relation is a function if every input (x-value) has exactly one output (y-value).

Step2: Check Option A

List coordinates: $(-4,7), (-2,5), (2,-1), (3,-1), (6,-5)$. All x-values are unique.

Step3: Check Option B

Table has $x=15$ paired with $y=2$ and $y=3$; $x=20$ paired with $y=4$ and $y=5$. Duplicate x-values with different y-values, so not a function.

Step4: Check Option C

Set has $x=-6$ paired with $y=5$ and $y=4$. Duplicate x-value with different y-values, so not a function.

Step5: Confirm valid option

Only Option A satisfies the function definition.

Answer:

A. (The coordinate graph with points $(-4,7), (-2,5), (2,-1), (3,-1), (6,-5)$)