Question

8/22
which of the following is a function?

x | f(x)
2 | -2
0 | 0
2 | 2
8 | 4

{(6, 1), (4, 2), (6, -3), (2, 5)}

Explanation:

A function is defined such that each input (x-value) has exactly one output (y-value).

1. Graph (top left): Passes the vertical line test—no vertical line intersects the graph more than once, so each x has one y.
2. Table (top right): The input x=2 maps to both -2 and 2, violating the function rule.
3. Ordered pairs (bottom left): The input x=6 maps to both 1 and -3, violating the function rule.
4. Mapping (bottom right): The input 5 maps to both 4 and -4, violating the function rule.

Answer:

The graph in the top-left box (the diagonal line on the coordinate grid) is a function.