x-Values y-Values

0 5
1 15
2 45
3 135
4 405
Select the function that best models the data and determine the value of the function at x=−1
.

(1 point)
Responses

f(x)=41.43x2−73.71x+19.86
; f(−1)=135
f of x is equal to 41 point 4 3 x squared minus 73 point 7 1 x plus 19 point 8 6; f of negative 1 is equal to 135

f(x)=5⋅3x
; f(−1)=53
f of x is equal to 5 times 3 to the x th power; f of negative 1 is equal to 5 thirds

f(x)=2.23⋅(1.40)x
; f(−1)=1.59
f of x is equal to 2 point 2 3 times 1 point 4 0 to the x th power ; f of negative 1 is equal to 1 point 5 9

f(x)=92x−63
; f(−1)=−155

1 answer

To determine which function best models the provided data and to calculate the value of the function at \( x = -1 \), we can analyze the given options.

The provided data points are:

  • \( (0, 5) \)
  • \( (1, 15) \)
  • \( (2, 45) \)
  • \( (3, 135) \)
  • \( (4, 405) \)

Let's evaluate the options one by one:

  1. Option 1: \( f(x) = 41.43x^2 - 73.71x + 19.86 \)

    • Let's test \( f(-1) \): \[ f(-1) = 41.43(-1)^2 - 73.71(-1) + 19.86 = 41.43 + 73.71 + 19.86 \approx 135 \quad (\text{Correct calculation}) \]
  2. Option 2: \( f(x) = 5 \cdot 3^x \)

    • Let's test \( f(-1) \): \[ f(-1) = 5 \cdot 3^{-1} = 5 \cdot \frac{1}{3} = \frac{5}{3} \approx 1.67 \]
  3. Option 3: \( f(x) = 2.23 \cdot (1.40)^x \)

    • Let's test \( f(-1) \): \[ f(-1) = 2.23 \cdot (1.40)^{-1} = 2.23 \cdot \frac{1}{1.40} \approx 1.59 \]
  4. Option 4: \( f(x) = 92x - 63 \)

    • Let's test \( f(-1) \): \[ f(-1) = 92(-1) - 63 = -92 - 63 = -155 \]

Next, we look at which function fits the given data points best. Analyzing the outputs as given, we notice:

  • The first function gives \( f(-1) = 135 \), which does not match how values typically function.
  • The second option, when \( x = -1 \), gives a value of approximately \( 1.67\).
  • The third option gives \( f(-1) \approx 1.59\).
  • The fourth option correctly gives \( f(-1) = -155 \).

In the context of potential modeling, the polynomial function \( f(x) = 41.43x^2 - 73.71x + 19.86 \) gives a critical fit for points mentioned for non-negative integers. Thus, the best choice of the model from a dataset perspective, specifically focusing on defining \( f(-1)\) to find its own functionalities when seeking insights into escalating patterns, retains remarkable contribution value.

Conclusively, among these formulations, the most fitting across formal selection would identify with \( f(-1) = 135 \) as quintessentially representing the polynomial expansion approach.

Final Answer:

Option 1: \( f(x) = 41.43x^2 - 73.71x + 19.86 \); \( f(-1) = 135 \).