SOLUTION: Find the exponential function f(x) = a^x that passes through the point (2,25) and has a y-intercept of 1. Find y = ?

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Question 1204988: Find the exponential function f(x) = a^x that passes through the point (2,25) and has a y-intercept of 1.
Find y = ?
Found 2 solutions by MathLover1, Theo:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Find the exponential function
f%28x%29+=+a%5Ex+
passes through the point (2,25)
has a y-intercept of 1

use given point to calculate a

25=+a%5E2
a=5
the exponential function is:
f%28x%29+=+5%5Ex+ or y=+5%5Ex+

+graph%28+600%2C+600%2C+-5%2C+5%2C+-5%2C+5%2C+5%5Ex%2C+5%5Ex%29+

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
let y = f(x).
your equation becomes y = a^x.
if it passes through the point (2,25), then you get 25 = a^2
solve for a to get a = 5.
your equation becomes y = 5^x
then x = 2, you get y = 25.
that's the point (2,25)
the y-intercept is the value of y when the value of x is 0.
y = 5^x becomes y = 5^0 which becomes y = 1 because x^0 is always equal to 1.