Question

look at this set of ordered pairs:
(11, 8)
(4, -15)
(8, 12)
(13, 8)
(18, 4)
(-5, 19)
is this relation a function?
yes no

Explanation:

Step1: Recall the definition of a function

A relation is a function if each input (x - value) has exactly one output (y - value). That is, no two ordered pairs in the relation can have the same first element (x - coordinate) with different second elements (y - coordinates).

Step2: Check the x - values of each ordered pair

• For the ordered pair \((11, 8)\), the x - value is \(11\).
• For the ordered pair \((4,- 15)\), the x - value is \(4\).
• For the ordered pair \((8,12)\), the x - value is \(8\).
• For the ordered pair \((13,8)\), the x - value is \(13\).
• For the ordered pair \((18,4)\), the x - value is \(18\).
• For the ordered pair \((-5,19)\), the x - value is \(-5\).

We can see that each x - value appears only once in the set of ordered pairs. So, each input has exactly one output.

Answer:

yes