Question

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a y=0.8 + 8.5x
b y=0.8 - 8.5x
c y=8.5 + 0.8x
d y=8.5 - 0.8x

Explanation:

Step1: Observe the trend of points

As \(x\) increases, \(y\) decreases, so the slope of the regression - line should be negative.

Step2: Analyze the \(y\) - intercept

When \(x = 0\), the \(y\) - value of the first point is around \(10\).

Step3: Check the equations

For option A \(y = 0.8+8.5x\), the slope is positive (\(8.5\)), so it's wrong. For option B \(y = 0.8 - 8.5x\), when \(x = 0\), \(y=0.8\) which is too small compared to the \(y\) - value at \(x = 0\) in the graph. For option C \(y = 8.5+0.8x\), the slope is positive (\(0.8\)), so it's wrong. For option D \(y = 8.5-0.8x\), the slope is negative (\(- 0.8\)) and when \(x = 0\), \(y = 8.5\) which is consistent with the graph's general trend and \(y\) - intercept.

Answer:

D. \(y = 8.5-0.8x\)