Posted by **Shay** on Wednesday, March 17, 2010 at 5:39pm.

Find the exponential model using y=a(b)^x with (9, 120) & (12, 216) (round to 4 decimal places- show work)

- Math (FST Exponential & Logarithm) -
**Reiny**, Wednesday, March 17, 2010 at 7:35pm
subbing in the 2 points gives us

1) 120 = a(b)^9

2) 216 = a(b)^12

divide 2) by 1)

216/120 = b^12/b^9

b^3 = 9/5

b = (9/5)^(1/3) = 1.2164

put this back into 1)

120 = a(1.2164)^9

a = 20.5761

y = 20.5764(1.2164)^x

(I checked for (12,216), it works)

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