SOLUTION: If the graph of {{{f(x)=b^x}}} asses through the point (2,9), find f(4)

Question 130631: If the graph of asses through the point (2,9), find f(4)
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Since the graph passes through the point (2,9), this means that when x=2, then y=9.

Start with the given equation

Plug in x=2 and y=9. Notice how the only unknown left is b

Take the square root of both sides to isolate b

Take the square root of to get b

Take the square root of 9 to get 3

So our equation becomes

Now to evaluate f(4), simply plug in x=4

Plug in x=4

Evaluate 3 to the fourth power to get 81

Since "y" is equivalent to f(x), this means that

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