Algebra 1
Name:___________________________
Unit 5 – LT 5
Unit 5 – Day 6 – Notes
Date:__________Period:______
Learning Target 5: I can interpret key parts of a graph including determining an appropriate domain in real world
applications.
1. The graph below represents the average salary of an MLB player (in millions) since 1984. Use the
graph to answer the following questions:
a.
Does this graph represent exponential growth or exponential decay? Explain how you know.
b.
Estimate the y-intercept: ______________________.
c.
What does the y-intercept represent in this situation?___________________________________
d.
Estimate the average salary 5 years after 1984: _________________________.
e.
Estimate the average salary in 1998: _________________________.
f.
Estimate the average salary this year_________________________.
g.
Use the graph above to complete the table on the right. You
may approximate when necessary.
h.
How much was the average salary in 1995?
Year
1984
1989
i) $7,500
ii) $75,000
1994
iii) $750,000
iv) $7,500,000
1999
2004
i.
Identify the end behavior of the graph.
as 𝑥 → −∞, 𝑓(𝑥) →_________
as 𝑥 → +∞, 𝑓(𝑥) →_________
2009
2014
Average Salary
2. The graph below represents the number of bacteria (in thousands) that develop over time (in
hours). Use the graph to answer the following questions:
a.
Does this graph represent exponential growth or exponential decay? Explain how you know.
b.
Estimate the y-intercept: ______________________.
c.
What does the y-intercept represent in this situation?___________________________________
d.
Estimate the number of bacteria after 15 hours: ______________________________.
e.
Estimate the number of bacteria after 2.5 hours: ______________________________.
f.
How long does it take for there to be 30,000 bacteria? _______________________________
g.
Approximately how many bacteria are there after 17 hours?
h.
i) 77
ii) 770
iii) 7,700
iv) 77,000
Identify the end behavior of the graph.
as 𝑥 → −∞, 𝑓(𝑥) →_________
as 𝑥 → +∞, 𝑓(𝑥) →_________
3. Batman is trying to save the city of Gotham! The population of Gotham is represented by the
function: 𝒇(𝒙) = 𝟐𝟐, 𝟕𝟑𝟗 ∙ 𝟏. 𝟎𝟐𝟓𝒙 where 𝒙 represents the number of years since 2000.
a. Use the function above to determine if the population is of Gotham is modeled by exponential
Years Since Population of
growth or exponential decay? How do you know? Use your function
2000
Gotham
to explain your answer.
-3
-1
0
2
5
b. Use the function to complete the following table of values:
c. What is the y-intercept? What does it represent in the situation?
d. What was the population of Gotham in 2010?
e. Evaluate f(15). Explain what it represents.
f. What was the population of Gotham in 1996?
9
Algebra 1
Unit 5 – LT 5
Name:___________________________
Unit 5 – Day 6 – Homework
Date:__________Period:______
Learning Target 5: I can interpret key parts of a graph including determining an appropriate domain in real world
applications.
1. The graph below represents the amount of money in Courtney’s bank account (in thousands) over
time (in years since 2002). Use the graph to answer the following questions:
a.
Does this graph represent growth or decay? Explain how you know.
b.
Identify the y-intercept:___________________
c.
What does the y-intercept represent in this situation?
d.
Estimate the amount of money in Courtney's bank account in 2004: ________________.
e.
Estimate the amount of money in Courtney's bank account in 2012: ________________.
f.
During what year does Courtney have $7,000? _______________________________
2. The following table represents the number of people in the “Words with Friends” tournament after
each round. For example, after the third round, 512 people remained in the tournament.
a. What do the x-values represent?
b. What do the y-values represent?
c. Does the table represent exponential growth or
exponential decay? Explain how you know.
d. Use the table to identify the exponential base, 𝑏.
e. Use your exponential base from part (d) to complete the table of values above..
f. Evaluate g(2). What does it represent?
g. If g(x) = 128, what is x? And what does it represent?
h. How many players are still left in the 8th round?
i. How many rounds is the tournament? (Hint: the final round has two people remaining)