we know that
The residual value is the observed value minus the predicted value.
RESIDUAL VALUE=[OBSERVED VALUE-PREDICTED VALUE]
where
Predicted value.--> the predicted value given the current regression equation
Observed value. --> The observed value for the dependent variable.
in this problem
the point (5,1) means that for x=5 the observed value is 1
predicted value for x=5 y=-0.2x+1.7-----> y=-0.2*5+1.7----> y=0.7
predicted value is 0.7
observed value is 1
so
RESIDUAL VALUE=[1-0.7]------> 0.30
the answer is
the residual value is 0.3