Graph Each Function

Name

Class

Date

Exploring Exponential Models

7-1

Practice

Form G

Graph each function.

1. 2. 3.

4. 5. 6.

Without graphing, determine whether the function represents exponential growth or exponential decay. Then find the y-intercept.

7. 8.

9. 10.

11. 12.

13.Supposeyoudeposit$1500inasavingsaccountthatpaysinterestatanannual rate of 6%. No money is added or withdrawn from the account.

a. Howmuchwillbeintheaccountafter5years?

b. Howmuchwillbeintheaccountafter20years?

c.Howmanyyearswillittakefortheaccounttocontain$2500?

d. Howmanyyearswillittakefortheaccounttocontain$4000?

Write an exponential function to model each situation. Find each amount after the specified time.

14. Apopulationof1,236,000grows1.3%peryearfor10years.

15. Apopulationof752,000decreases1.4%peryearfor18years.

16. Anewcarthatsellsfor$18,000depreciates25%eachyearfor4years.

Prentice Hall Algebra 2 •Teaching Resources

Name

Class

Date

Exploring Exponential Models

7-1

Practice (continued)

Form G

For each annual rate of change, find the corresponding growth or decay factor.
17. + 45%18. − 10%19. − 40%20. + 200%

21. + 28%22. + 100%23. −5%24. + 3%

25. In2009,therewere1570bearsinawildliferefuge.In2010,thepopulationhad increased to approximately 1884 bears. If this trend continues and the bear population is increasing exponentially, how many bears will there be in 2010?

26.Thevalueofapieceofequipmenthasadecayfactorof0.80peryear.After 5 years, the equipment is worth $98,304. What was the original value of the equipment?

27.Yourfrienddropsarubberballfrom4ft.Younoticethatitsreboundis 32.5 in. on the first bounce and 22 in. on the second bounce.

a.Whatexponentialfunctionwouldbeagoodmodelfortheheightofthe ball?

b.Howhighwilltheballbounceonthefourthbounce?

28.Aninvestmentof$75,000increasesatarateof12.5%peryear.Whatisthe value of the investment after 30 years?

29. Anewtruckthatsellsfor$29,000depreciates12%eachyear.Whatisthevalue of the truck after 7 years?

30. Thepriceofanewhomeis$350,000.Thevalueofthehomeappreciates2% each year. How much will the home be worth in 10 years?

31. Thepopulationofanendangeredbirdisdecreasingatarateof0.75%peryear. There are currently about 200,000 of these birds.

a.Whatexponentialfunctionwouldbeagoodmodelforthepopulationof
these endangered birds?

b.Howmanybirdswilltherebein100years?

Prentice Hall Algebra 2 •Teaching Resources