Question

Look at this table:

x y
20 12
0 19
18 7
0 –13

Is this relation a function?

Answer 1

To determine if the relation is a function, we need to check if each input value (x) corresponds to exactly one output value (y). In a function, no two different ordered pairs can have the same first element (x-value).

Let’s examine the given pairs:

1. (20, 12)
2. (0, 19)
3. (18, 7)
4. (0, –13)

Here, the x-values are 20, 0, 18, and 0 (from the last two pairs). The x-value 0 appears in two different pairs: (0, 19) and (0, –13) and corresponds to two different y-values (19 and -13).

Since the same x-value (0) is associated with two different y-values, this relation is **not a function**.