To find the equation of the trend line in slope-intercept form \( y = mx + b \), we need to determine the slope \( m \) and the y-intercept \( b \).
From the points provided:
- The line passes approximately through the points (0, 9) and (10, 6.5).
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Finding the slope (m): The slope \( m \) is calculated using the formula: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \] Using the points (0, 9) and (10, 6.5): \[ m = \frac{6.5 - 9}{10 - 0} = \frac{-2.5}{10} = -0.25 \]
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Finding the y-intercept (b): Since we know the line passes through (0, 9), we can see that the y-intercept \( b \) is 9.
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Writing the equation: Substitute \( m \) and \( b \) into the slope-intercept form: \[ y = -0.25x + 9 \]
In fraction form, \( -0.25 = -\frac{1}{4} \), so the equation can be written as: \[ y = -\frac{1}{4}x + 9 \]
Thus, the correct response is: y = -\frac{1}{4}x + 9.