posted by Viggo .
How do you do this:
Write an exponential function of the form y=ab^x that has a graph through (-2, 25) and (1, 10).
This is what I have so far:
Then I am stuck. Am I doing it right so far? How do I continue? Thanks!
I don't get your second last line, I had:
25 = (10/b)b^-2
2.5 = b^-3
0.4 = b^3
then a=10/.7368... = 13.572..
so y = 13.572(.7368)^x
I checked both data values, they work