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The municipal swimming pool in Nicetown has three different ways of paying for individual open swimming. Evan is trying to decide which way to pay.
• Early Pay: Pay \$45 before Memorial Day; swim any number of days
• Deposit Plus: \$20 deposit plus \$2.00 per day
• Daily Pay: \$3.50 per day

1. Write an equation for each situation such that the cost, y, of swimming is a function of the number of days swimming, x. The ordered pairs will be in the form, (x, y), and you can write your equations in slope-intercept form.
a. Early Pay:
b. Deposit Plus:
c. Daily Pay:

2. Fill in the table with the costs of swimming the given number of days.
Table of swimming costs using the three different payment methods
Payment Method Number of days 0 days 10 days 12 days 14 days 20 days
Early Pay
Deposit Plus
Daily Pay

3. On your own (ungraded), graph each equation on the same set of axes so you can visually compare the payment methods. Let the horizontal axis be the number of days swimming, x, and the vertical axis the cost in dollars, y.

4. If Evan goes swimming 10 times, which is the best payment method for him, and how much will he have to pay?

5. If Evan goes swimming 12 times, which is the best method for him, and how much will he have to pay?

6. If Evan goes swimming 14 times, which is the best method for him, and how much will he have to pay?

7. If Evan doesn’t know how many times he will go swimming, which method do you think he should choose and why?

I'll get you started:

a. Early Pay: y = 45.00
b. Deposit Plus: y = 20.00+2.00x
c. Daily Pay: y = 3.50x

Now, plug in your numbers, and come back if you get stuck.

ok i put the answers in.. now what

for #3, try going to

rechneronline . de/function-graphs/

and graph each function above.

For #4,5,6 take a look at your table and answer the questions. You should have a row or column for 10 days, 12 days, 14 days, etc. Look up the y-values for the given number of days.