Constructing Exponential Functions

What is the value of b in the exponential function of the graph?

• 3

• 0.5

• 6

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x

• y = 15(1.35)^x

• y = 15(0.35)^x

• y = 35(1.15)^x

Is the pictured graph growth, decay, or linear or none?  

• Exponential Growth

• Exponential Decay

• Linear

• None

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Create the exponential function with the following attributes:

Asymptote: y = 0

Initial value: 3

Point on the graph: (2, 6)

Growth

There were 417 cell phones sold at an electronics store in January. Since then, cell phone sales at this store have increased at a rate of 3.75% per month. At this rate of growth, which function can be used to determine the monthly cell phone sales x months after January?

What is the equation of the graph shown, and what is the y-intercept?

• y = 1⁄3 (3)^x ; (0, 1⁄3)

• y = 1⁄3 (3)^x ; (0, 3)

• y = 3 (1/3)^x ; (0, 1⁄3)

• y = 3 (1/3)^x ; (0,3)

What is the equation of the graph shown, and what is the y-intercept?

• y = 1⁄3 (3)^x ; a = 1⁄3

• y = 1⁄3 (3)^x ; a = 3

• y = 3 (1/3)^x ; a = 1⁄3

• y = 3 (1/3)^x ; a = 3

A shipping company started with 40 employees. The number of employees in the shipping company increases at a rate of 7.5% each year. What function can be used to model the number of employees, f(x), in the shipping company after x years?

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x

• y=30(5000)^x

• y=5000(1.3)^x

• y=5000x^x