Exponential Decay Functions

Terrence buys a new car for $20,000. The value of the car depreciates by 15% each year. If f(x) represents the value of the car after x years, which function represents the car’s value?

• f(x) = 20,000(0.85)^x

• f(x) = 20,000(0.15)^x

• f(x) = 20,000(1.15)^x

• f(x) = 20,000(1.85)^x

Tags

CCSS.HSF.LE.A.2

Ginny is studying a population of frogs. She determines that the population is decreasing at an average rate of 3% per year. When she began her study, the frog population was estimated at 1,200. Which function represents the frog population after x years?

• f(x) = 1,200(1.03)^x

• f(x) = 1,200(0.03)^x

• f(x) = 1,200(0.97)^x

• f(x) = 1,200(0.97)^x

Tags

CCSS.HSF.LE.A.2

A population of bacteria is treated with an antibiotic. It is estimated that 5,000 live bacteria existed in the sample before treatment. After each day of treatment, 40% of the sample remains alive. Which best describes the graph of the function that represents the number of live bacteria after x days of treatment?

• f(x) = 5000(0.4)x, with a horizontal asymptote of y = 0

• f(x) = 5000(0.6)x, with a vertical asymptote of x = 0

• f(x) = 5000(1.4)x, with a horizontal asymptote of y = 0

• f(x) = 5000(1.6)x, with a vertical asymptote of x = 0

Tags

CCSS.HSF.LE.A.2

Which graph represents exponential decay?

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Tags

CCSS.HSF-IF.C.7E

Chelsea is graphing the function f(x) = 20(1/4)x. She begins by plotting the initial value. Which graph represents her first step?

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Tags

CCSS.HSF-IF.C.7E

Which is the graph of f(x) = 100(0.7)x?

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Tags

CCSS.HSF-IF.C.7E

What is the multiplicative rate of change of the function?

• 1/5

• 2/5

• 2

• 5

Tags

CCSS.HSF-LE.A.1B

What is the multiplicative rate of change of the function?

• .2

• .25

• .5

• .75

Tags

CCSS.HSF-LE.A.1C

The table represents an exponential function.

What is the multiplicative rate of change of the function?

• 1/3

• 2/3

• 2

• 9

Tags

CCSS.HSF-LE.A.1A

What does the graph represent?

• Exponential Decay

• Exponential Growth

Tags

CCSS.HSF-IF.C.7E