Exponential Functions Characteristics

Identify the y-intercept (initial value) in the function f(x)=13(.27)^x

• (.27)^x
• .27
• 13
• 3.51

Describe the equation
y = 100 * 2^x

• It starts with 100 and is tripling

• It starts with 100 and is doubling

• It starts with 2 and is being multiplied by 100 each time

• It starts with 100 and is adding 2 each time

Linear, exponential, or neither?

• Linear

• Exponential

• Neither

• All of the above

Write an equations that models the data shown.

What is the y-intercept of the function?

• 2

• 3

• 1

• -2

Does the graph represent an exponential growth or an exponential decay function?

• Exponential Growth

• Exponential Decay

What does the y-intercept of the graph represent?

• The amount of grams the material is gaining.

• The amount of grams the material is losing.

• The amount of grams remaining after so many years.

• The initial amount of grams.

Which of the following is an increasing exponential function whose y-intercept is 50?

• y = 50(.05)^x

• y = 50x - 4

• y = (2)^x + 50

• y = 50(1.4)^x

The amount of ants in a colony, f, that is decaying can be modeled by                      f(x) = 800(.87)^x, where x is the number of days since the decay started. By what percentage is the colony decaying?

• 87%

• 13%

• 800%

• 8.7%

The amount of ants in a colony, f, that is decaying can be modeled by                         f(x) = 800(.87)^x, where x is the number of days since the decay started. Suppose           f(20) = 49. Which of the following is true?

• After 20 days, there are 49 ants in the colony.

• After 49 days there are 20 ants in the colony.

• The amount of ants times 20 is 49.

• After 20 days the amount of ants remaining decreases by 49.