Question

Norma made the graph below to show the relationship between the age and value of 12 cars. Which value, when removed from the graph, would result in the relationship being a function?

Answer 1

$3,000 (3 from the y-axis)

Explanation:

For a relationship to be considered a function, every domain value (x-value) must have exactly one range value (y-value) related to it.

Therefore, for the relationship between age and the value of 12 cars to be considered a function, every age of a car (domain value) must have exactly one particular value in dollars (range value).

From the graph, we can see that age of car of 7 years (x-value/domain value) has two different values of $3,000 and $5,000 (y-value/range value) which doesn't make the the relationship a function.

Therefore, if we remove $3,000 (on the y-axis) from the graph, the relationship will be a function.

We would now have each domain value having exactly one range value.