Use the image to answer the question.

A scatterplot graph shows x-axis ranging from 0 to 50 and y-axis ranging from 0 to 10. Multiple points are plotted around a line that points downward to the right with an arrowhead on the bottom.
The x-axis is drawn in increments of 5 but labeled in increments of 10. The y-axis is drawn in increments of 1 but labeled in increments of 2. The line passes approximately through left parenthesis 0 comma 8 right parenthesis, left parenthesis 10 comma 6 right parenthesis, left parenthesis 15 comma 5 right parenthesis, left parenthesis 20 comma 4 right parenthesis, left parenthesis 25 comma three right parenthesis, and left parenthesis 40 comma 0 right parenthesis. 14 points are plotted close to or on the line.

Write an equation in slope-intercept form of the trend line.

(1 point)
Responses

y=5.67x+8
y equals 5.67 x plus 8

y=15x+8
y equals Start Fraction 1 over 5 End Fraction x plus 8

y=−15x+3
y equals negative Start Fraction 1 over 5 End Fraction x plus 3

y=−15x+8
y equals negative Start Fraction 1 over 5 End Fraction x plus 8
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1 answer

To write 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, we can identify two points on the trend line, for example, the points \((0, 8)\) and \((40, 0)\).

  1. Finding the slope \(m\): The formula for the slope \(m\) between two points \((x_1, y_1)\) and \((x_2, y_2)\) is given by: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \] Using the points \((0, 8)\) and \((40, 0)\): \[ m = \frac{0 - 8}{40 - 0} = \frac{-8}{40} = -\frac{1}{5} \]

  2. Finding the y-intercept \(b\): The y-intercept \(b\) is the value of \(y\) when \(x = 0\). From the point \((0, 8)\), we see that: \[ b = 8 \]

  3. Writing the equation: Substituting \(m\) and \(b\) into the slope-intercept form: \[ y = -\frac{1}{5}x + 8 \]

Now we compare this with the provided options.

The correct equation is: \[ y = -\frac{1}{5}x + 8 \] This matches the option:

  • \(y = -15x + 8\) (the slope should be \(-\frac{1}{5}\), not \(-15\)).

There seems to be a mistake in the option's representation. The correct slope should indicate the \( -\frac{1}{5} \) rather than saying \(-15\), which is not adequate.

Therefore, based on the accurate calculations, the final correct answer for the slope-intercept form, based on the options provided, is: None of the options are correct. The right equation based on our calculation is \(y = -\frac{1}{5}x + 8\).