Question 513446
Write the exponential function of the data. 

x: 0, 5, 10 
G(x) 100, 90, 81 
so, (0, 100), (5, 90), (10, 81) 

I got an equation of g(x) = 100 * .979^x using stat list on my graphing calculator. I want to know how to do this question without a calculator. 

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Using the points (0,100) and (5,90)
Form: 
y = ab^x ; solve for "a" and "b".
100 = ab^0
100 = a*1
a = 100
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So, y = 100b^x
Solve for "b" using (5,90):
90 = 100*b^5
b = 0.9^(1/5) = 0.9791
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y = 100*0.9^(x/5)
OR
y = 100*0.9791^x
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Cheers,
Stan H.
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