Let's begin by making a table of the residual values. Note that, in our table, y represents the growth in inches of an elk's antlers in week x.
x
y
y=-0.7x+6.8
y-value From Model
Residual
1
6.0
-0.7( 1)+6.8
6.1
6.0-6.1= -0.1
2
5.5
-0.7( 2)+6.8
5.4
5.5-5.4= 0.1
3
4.7
-0.7( 3)+6.8
4.7
4.7-4.7= 0
4
3.9
-0.7( 4)+6.8
4.0
3.9-4.0= -0.1
5
3.3
-0.7( 5)+6.8
3.3
3.3-3.3= 0
Now we can create a scatter plot using the given x-values and our residuals. Remember, if the model is a good fit for the data, the scatter plot will be evenly distributed above and below the x-axis. Also, there will be no apparent patterns.
This line of fit models the data well. It is evenly distributed above and below the x-axis.
