A student creates a function to represent the cost of pencils available for purchase at the school store. The school charges 5 cents per pencil for up to 20 pencils. What is the domain of the function?
A.) all integers from 0 to 20
B.) all real numbers from 0 to 20
C.) all integer multiples of 5 from 5 to 100
D.) all real number multiples of 5 from 5 to 100
Since, we can only use integers such as 1, 2, 3, ... in order to count for the number of pencils that is purchased. The domain of the equation is essentially the values of x that can be used. In this example, the answer is letter A.
