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Question

Write an exponential equation that models this function: {(1, 5), (2, 10), (3, 20), (4, 80)} Note: The general formula for an exponential function is y = a(b)^x, where a = initial value of the function (when x = 0), b = constant ratio between consecutive y-values.

Answer 1

Since the y values are doubling, that tells you that b=2. To solve for the a value, plug in one of the points given. I will use the first point (1,5)

5=a(2)¹ Simplify

5=2a Divide both sides by 2

5/2=a

Equation is:

y=5/2(2)^x

Answer 2

exponential regression says:

y = 1.767766953 * 2.462288827^x