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Part 1
The points​ (2,54.61) and​ (4,403.48) are points on the graph of an exponential model of the form y.
a. Explain how to write the exponential​ model, and then write the model.
b. How can you use the exponential model to find the value of y when x​8?
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Part 1
a. Select the correct answer below and fill in the answer box to complete your choice.

1 Answer

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The exponential model can be written in the form y = ab^x, where a and b are constants.

To find the values of a and b, we can use the given points (2, 54.61) and (4, 403.48).

Let's start with point (2, 54.61). Substituting the x and y values into the exponential model equation, we get:

54.61 = ab^2

Next, let's use the second point (4, 403.48). Substituting the x and y values into the exponential model equation, we get:

403.48 = ab^4

We now have a system of equations:

54.61 = ab^2

403.48 = ab^4

To solve this system, we can divide the second equation by the first equation:

(403.48)/(54.61) = (ab^4)/(ab^2)

Simplifying, we get:

7.39 = b^2

Taking the square root of both sides, we find:

b ≈ √7.39

To find the value of a, we can substitute the value of b back into one of the original equations. Let's use the first equation:

54.61 = a(√7.39)^2

Simplifying, we get:

54.61 = a(7.39)

Dividing both sides by 7.39, we find:

a ≈ 54.61/7.39

Now we have the values of a and b:

a ≈ 7.39

b ≈ √7.39

So, the exponential model is approximately y = 7.39(√7.39)^x.

Now, let's move on to part b. To find the value of y when x = 8, we can substitute x = 8 into the exponential model equation:

y = 7.39(√7.39)^8

Calculating this expression will give us the value of y when x = 8.

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