Question

Genesis would like to join a Book Club. She needs to pay $12.00 for entrance into the book

club and $20.00 per month. Write an equation in function notation for the total cost of the book
club.

Answer 1

An equation in function notation for the total cost of the book club will be:

• y = 20x + 12

Explanation:

Given that Genesis needs to pay $12.00 for entrance into the book club.

Per month fee = $20.00

We know that the slope-intercept form of a linear function is

`y = mx+b`

where m is the slope and b is the y-intercept

As the rate of change is also called the slope.

The rate of $20.00 per month would be termed as the slope = m = 20

One time fee = $12.00, meaning the y-intercept = b = 12

Thus, the equation becomes

`y = mx+b`

• y represents the total cost

• x represents the duration

• m represents the rate of change = m = 20

• b represents the y-intercept = b = 12

y = 20x + 12

Therefore, an equation in function notation for the total cost of the book club will be:

• y = 20x + 12