SOLUTION: write an exponential function y=ab^x with (-1,8 1/3) and (2, 1.8)

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Question 942581: write an exponential function y=ab^x with (-1,8 1/3) and (2, 1.8)
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
write an exponential function y=ab^x with (-1,8 1/3) and (2, 1.8)
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Form: y = ab^x
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Solve for a and b
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1.8 = ab^2
25/3 = ab^-1
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Divide and solve for "b"::
0.216 = b^3
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b = 0.6
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Now solve for "a"::
1.8 = a*0.6^2
1.8 = a*0.36
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a = 5
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Ans: y = 5*(0.6)^x
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Cheers,
Stan H.
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