Concept explainers
In Exercises 49–54, assume that a constant rate of change exists for each model formed.
Bridges Needing Repair. The number of U.S. bridges in need of repair has been declining recently. In 2000, 89,460 bridges were labeled structurally deficient. By 2016, this number had dropped to 56,000. Let
Data: U.S. Department of Transportation; The Wall Street Journal, “Maligned Bridges Get Needed Repair” by
a. Find a linear function that fits the data.
b. Use the function of part (a) to estimate the number of bridges in need of repair in 2008.
c. At this rate of decrease, when will the number of bridges in need of repair reach 48,000?
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- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:Cengage