Functions or not

Question

The relation between earnings and sales if Olwen earns $400 per week plus 5% commission on sales.

 

Determine if this relation is a function.

Answer 1

Let y equal how much he makes in total for a week.  Let x = the number of items he sells.

 

y = (.05) (x)  + 400

 

It is a function. a function is: a relationship or expression involving one or more variables