1. WARM UP-do not write on the white description sheets --TAKE A SHEET OF PAPER, A NOTE CARD FROM THE STOOL, TAKE OUT COLOR PENCILS FROM THE BOX BELOW YOUR SEAT(pick out one pencil you would like to use) AND READ SILENTLY.

2. WARM UP Create a bio and include the following Best Attribute: Appearance: Hidden Talent: Shortcomings: Quote:

3. Section 9-7: Exponential Growth & Decay

4. 9/12/2015Section 8-8 Growth vs. Decay Growth Increase Investment Grows Appreciates Decay Decreases Depreciates Half Life

5. 9/12/2015Section 8-8 Exponential Growth y = a ∙ (1 + r) x initial amount (when x = 0) growth factor (expressed as a decimal) time frame (days, months, years, etc.)

6. 9/12/2015Section 8-8 Growth and Decay If the number in the parenthesis is greater than 1, it is exponential growth Example: y = 3(1.7) t If the number in the parenthesis is less than 1, it is exponential decay. Example: y = 2(0.5) t

7. 9/12/2015Section 8-8 y = a ∙ (1 + r ) x You have a Visa card with a balance of $1,500. Visa is charging you an interest rate of 1.5 % per month. How much will you owe after one year? (Assuming you make no payments).

8. 9/12/2015Section 8-8 Your turn The student population at Topsail High School is growing by 5% per year. If the current student body is 920 students, what is the predicted population in 3 years when you graduate?

9. 9/12/2015Section 8-8 One more time… Compound interest: Your parents deposited $1500 in an account paying 6.5% annual interest compounded annually when you were born. Find the account balance after 18 years. How much would be in the account if the interest was compounded quarterly?

10. 9/12/2015Section 8-8 y = a ∙ (1 – r) x Half-life: The half-life of iodine-124 is 4 days. A technician measures a 40-mCi sample of iodine-124. a) How much iodine-124 is left in the sample after 4 days? b) How many half-lives occur in 16 days? c) How much iodine-124 is left in the sample after 16 days?

11. 9/12/2015Section 8-8 Your turn You buy a used car for $18,000. The car loses 12% of its value each year due to depreciation. Find the value of the car after 5 years & 10 years.