Use the table to answer the question.

x-values y-values
−1
6
0 5
1 6
2 9
3 14
Create a quadratic model for the dataset in the xy
-chart.

(1 point)
Responses

f(x)=2x+5
f left parenthesis x right parenthesis equals 2 x plus 5

f(x)=x+5
f left parenthesis x right parenthesis equals x plus 5

f(x)=x2+5
f left parenthesis x right parenthesis equals x squared plus 5

f(x)=x2+7

1 answer

To create a quadratic model for the given dataset, we need to find a quadratic function of the form \( f(x) = ax^2 + bx + c \) that fits the data points.

Let's analyze the data:

  • For \( x = -1 \), \( y = 6 \)
  • For \( x = 0 \), \( y = 5 \)
  • For \( x = 1 \), \( y = 6 \)
  • For \( x = 2 \), \( y = 9 \)
  • For \( x = 3 \), \( y = 14 \)

We can start by substituting the known points into the quadratic equation and solving for the coefficients \(a\), \(b\), and \(c\).

Using points:

  1. \( (-1, 6) \): \( 6 = a(-1)^2 + b(-1) + c \) → \( 6 = a - b + c \) → (Equation 1)
  2. \( (0, 5) \): \( 5 = a(0)^2 + b(0) + c \) → \( 5 = c \) → (Equation 2)
  3. \( (1, 6) \): \( 6 = a(1)^2 + b(1) + c \) → \( 6 = a + b + c \) → (Equation 3)

From Equation 2, we have \( c = 5 \). Substituting this into Equations 1 and 3 gives us:

  • For Equation 1: \( 6 = a - b + 5 \) → \( a - b = 1 \) → (Equation 4)

  • For Equation 3: \( 6 = a + b + 5 \) → \( a + b = 1 \) → (Equation 5)

Now we can solve Equations 4 and 5: From Equation 4 \( a - b = 1 \) and from Equation 5 \( a + b = 1 \).

Adding these two equations: \( (a - b) + (a + b) = 1 + 1 \) → \( 2a = 2 \) → \( a = 1 \).

Substituting \( a = 1 \) back into Equation 5: \( 1 + b = 1 \) → \( b = 0 \).

Now we have \( a = 1, b = 0, c = 5 \). Thus, the quadratic model is: \[ f(x) = x^2 + 5 \]

Looking at the responses provided:

  • \( f(x) = x^2 + 5 \)

This is the correct quadratic model for the dataset.

The correct response is: f(x) = x² + 5