Concept explainers
Cocaine Use The percent of high school seniors during the years 1975–2010 who have ever used cocaine can be described by
where x is the number of years after 1975.
a. What inputs correspond to the years 1975 through 2010?
b. What outputs for y could be used to estimate the percent of seniors who have ever used cocaine?
c. Based on your answers to parts (a) and (b), choose an appropriate window and graph the equation on a graphing utility.
d. Graph the function again with a new window that gives a graph nearer the center of the screen.
e. Use this function to estimate the percent in 2013.
(Source: monitoringthefuture.org)
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MYLAB MATH COLLEGE ALGEBRA IN CONTEXT
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