Page 767 - Algebra 1

_1 x _1 x
17. Predict Graph the functions f(x) = 100(2 ) and g(x) = 50 (2 ) . How
does the value of k in each equation compare to the y-intercept? How does the k-value affect the graph of the function?
Match the following exponential growth and decay equations to the graphs shown. Explain your choices.
18. y = 2(0.5)x 19. y = 2(3)x 20. y = (0.25)x 21. y = 0.25(2)x
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Graph C
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Investigation Practice
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a. Formulate Alex invested $500 in an account that will double his balance every 8 years. How many times will the amount in the account double in 32 years? Write an equation to model the account balance y after x doubling times. What will his balance be in 32 years?
b. Formulate Radioactive glucose is used in cancer detection. It has a half-life of 100 minutes. How many half-lives are in 24 hours? Write an equation to model the amount y remaining of a 100 milligram sample after x half-lives. How much of a 100 milligram sample remains after 24 hours?
Use the equation f(x) = _1 x to answer each problem. (2)
c. Does the equation model exponential growth or exponential decay? Explain.
_1 x
d. How does the graph of f(x) = (2) compare to the graph of g(x) = (3) ?
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e. How does the graph of f(x) = (2) compare to the graph of h(x) = 2 ?
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Saxon Algebra 1
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