Use the table to answer the question.

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)=92x−63
; f(−1)=−155
f of x is equal to 92 x minus 63; f of negative 1 is equal to negative 155

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)=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)=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
Question 2
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1 answer

To determine which function best models the given data, we need to analyze the pattern in the provided \( x \)-Values and \( y \)-Values. Let's look at the data:

| x-Values | y-Values | |----------|----------| | 0 | 5 | | 1 | 15 | | 2 | 45 | | 3 | 135 | | 4 | 405 |

Observing the \( y \)-Values, we can see that:

  • Each \( y \)-Value seems to be multiplied by 3 as we move from one \( x \)-Value to the next:
    • \( 5 \times 3 = 15 \)
    • \( 15 \times 3 = 45 \)
    • \( 45 \times 3 = 135 \)
    • \( 135 \times 3 = 405 \)

This suggests that the function may be exponential.

The second response suggests a function of the form:

\( f(x) = 5 \cdot 3^x \)

Let's evaluate this function at \( x = -1 \):

\[ f(-1) = 5 \cdot 3^{-1} = 5 \cdot \frac{1}{3} = \frac{5}{3} \]

The other responses can be ruled out based on the multipliers or degree of the polynomial when analyzed correctly against the generated \( y \)-values.

Thus, the function that best models the data is:

f(x) = 5 ⋅ 3^x; f(−1) = \frac{5}{3}

Final Answer:

f(x) = 5⋅3^x; f(−1) = 5/3