Answer:
-2.5
Explanation:
First, we need to know what is the residual is
The residual is the vertical distance between the regression line and a data point. If the distance is positive, the point is above the line and vice versa if the distance is negative, the point is below the point.
In this question, at x= 4 the we have the value is 2 but the value on the line is 4.5 so the vertical distance is:
2-4.5 =-2.5
As the data point lie below the regression line. hence the residual value will be negative. So we choose -2.5
Hope it will find you well.