EBK PRECALCULUS:GRAPHICAL,...-NASTA ED.
EBK PRECALCULUS:GRAPHICAL,...-NASTA ED.
10th Edition
ISBN: 9780135795910
Author: Demana
Publisher: PEARSON CO
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Chapter P.4, Problem 50E
Solution

To estimate American’s income in 2010, 2013, and 2015.

  in 2010, income was $12.5 trillion,in 2013, income was $14.2 trillion,in 2015, income was $15.4 trillion.

Given:

The equation that models the Americans’ income is, y=0.58x2010+12.5 , where x is the year.

Concept Used:

  • The slope-intercept form of a line is y=mx+b, where m is the slope of the line and b is the y -intercept of the line.
  • Slope of the line passing through the points x1,y1 and x2,y2 is given by m=y2y1x2x1
  • The slope of a line is defined as rise over run

Calculation:

In order to find the Americans’ income in 2010, substitute x=2010 into the given equation and simplify further as shown below,

  y=0.58x2010+12.5y=0.5820102010+12.5y=0.580+12.5y=0+12.5y=12.5

Thus, the Americans, income in 2010 is 12.5 trillion dollars.

By following the same procedure, using the linear equation the income in 2013 is 14.2 trillion dollars and in 2015 it was 15.4 trillion dollars.

Chapter P Solutions

EBK PRECALCULUS:GRAPHICAL,...-NASTA ED.

Ch. P.1 - Prob. 1ECh. P.1 - Prob. 2ECh. P.1 - Prob. 3ECh. P.1 - Prob. 4ECh. P.1 - Prob. 5ECh. P.1 - Prob. 6ECh. P.1 - Prob. 7ECh. P.1 - Prob. 8ECh. P.1 - Prob. 9ECh. P.1 - Prob. 10ECh. P.1 - Prob. 11ECh. P.1 - Prob. 12ECh. P.1 - Prob. 13ECh. P.1 - Prob. 14ECh. P.1 - Prob. 15ECh. P.1 - Prob. 16ECh. P.1 - Prob. 17ECh. P.1 - Prob. 18ECh. P.1 - Prob. 19ECh. P.1 - Prob. 20ECh. P.1 - Prob. 21ECh. P.1 - Prob. 22ECh. P.1 - Prob. 23ECh. P.1 - Prob. 24ECh. P.1 - Prob. 25ECh. P.1 - Prob. 26ECh. P.1 - Prob. 27ECh. P.1 - Prob. 28ECh. P.1 - Prob. 29ECh. P.1 - Prob. 30ECh. P.1 - Prob. 31ECh. P.1 - Prob. 32ECh. P.1 - Prob. 33ECh. P.1 - Prob. 34ECh. P.1 - Prob. 35ECh. P.1 - Prob. 36ECh. P.1 - Prob. 37ECh. P.1 - Prob. 38ECh. P.1 - Prob. 39ECh. P.1 - Prob. 40ECh. P.1 - Prob. 41ECh. P.1 - Prob. 42ECh. P.1 - Prob. 43ECh. P.1 - Prob. 44ECh. P.1 - Prob. 45ECh. P.1 - Prob. 46ECh. P.1 - Prob. 47ECh. P.1 - In Exercises 4752, simplify the expression. Assume...Ch. 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