Question 187584
I have seen this problem on here but I am not understanding why they use zero for "n" also I do not understand how to graph this.
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n=0 represents the number of years after 1990 when the year IS 1990.
So n=0 IS the year 1990
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Dental Services: The national cost C in billions of dollars for dental services can be modeled by the linear equation C = 2.85n + 30.52, when n is the number of years since 1990.
(a) Find and interpret the C-intercept for the line.
Let n=0, then C(0) = 2.85*0 + 30.52 = 30.52
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(b) Find and interpret the n-intercept for the line.
Let C = 0 and solve for "n":
2.85n + 30.52 = 0
2.85n = -30.52
n = -10.708
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(c) Graph the line for n ranging from 0 through 20.
{{{graph(400,300,-5,35,-10,120,2.85x + 30.52)}}}
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(d) If this trend continues, then in what year will the cost of dental services reach 100 billion?
2.85n + 30.52 = 100
2.85n = 69.48
n = 24.3789
Year: 1990+24.3789 = 2014.3789
Rounding up the year is 2015.
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Cheers,
Stan H.