Answer: -6.5
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Step-by-step explanation:
For the x value x = 3, the observed y value is y = 6 which is from the point (3,6).
The predicted y value is found by plugging x = 3 into the line of best fit equation
y = 5x-2.5
y = 5(3)-2.5
y = 12.5
The residual is the difference between the two y values
e = residual
e = (observed y value) - (predicted y value)
e = 6 - 12.5
e = -6.5
The negative residual tells us the observed y value is smaller than the predicted y value for this given x value.