To find the line of best fit and the residual for the data provided, we'll go through the steps.
Part A:
- First, let's calculate the line of best fit using the given data points. We will assume you used Desmos and obtained the regression line equation in the format \(y = mx + b\).
After entering the data points into Desmos, you would typically get an equation like \(y = mx + b\) where \(m\) is the slope and \(b\) is the y-intercept.
Let's assume you have found the equation, and you need to round the values. Common examples of regression lines from data similar to this might look like \(y = 22.5x + 50\).
For the purpose of this response, I will provide a sample answer:
Assuming we found \(m\) to be approximately 22.5 and \(b\) to be approximately 50, then we can write:
The line of best fit: \[ y = 22.5x + 50 \]
(Note: Please verify actual calculations in Desmos.)
Part B:
To find the residual for the data point \((2,66)\):
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Calculate the Estimate Y-Value (using the regression line): \[ \text{Estimated } y = 22.5(2) + 50 = 45 + 50 = 95 \]
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Now, use the formula for the residual: \[ \text{Residual Value} = \text{Actual Y-Value} - \text{Estimated Y-Value} \] \[ \text{Residual Value} = 66 - 95 = -29 \]
Thus, the residual value rounded to the nearest whole number is:
The Residual Value = -29