To solve this problem you must apply the proccedure shown below:
1- You must apply the following formula:
[tex] R=yo-yp [/tex]
Where[tex] R [/tex] is the residual, [tex] yo [/tex] is the observed value [tex] y [/tex] and [tex] yp [/tex] is the predicted value [tex] y [/tex].
2- You only need to substitute the [tex] x=5 [/tex] into the equation [tex] y=2.5x-1.5 [/tex] and then, you must apply the formula for calculate the residual:
[tex] y=2.5(5)-1.5\\ y=11 [/tex]
[tex] R=12-11\\ R=1 [/tex]
The answer is: The residual is [tex] 1 [/tex]
