Concept explainers
Life Sciences
45. Birds The date of the first sighting of robins has been occurring earlier each spring over the past 25 years at the Rocky Mountain Biological Laboratory. Scientists from this laboratory have developed two linear equations that estimate the date of the first sighting of robins:
where x is the year and y is the estimated number of days into the year when a robin can be expected. Source: Proceedings of the National Academy of Science.
- (a) Compare the date of first sighting in 2000 for each of these equations. (Hint: 2000 was a leap year.)
- (b) Solve this system of equations to find the year in which the two estimates agree.
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Finite Mathematics and Calculus with Applications (10th Edition)
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