Chapter 4 - Section 4.2 - Assess Your Understanding - Vocabulary and Skill Building - Page 215: 10f

$Σresidual^2=0.875$

Since $ŷ =−1.75x+3.5$ $Σresidual^2=Σ(y_i-ŷ _i)^2=Σ[y_i-(−1.75x_i+3.5)]^2=Σ(y_i+1.75x-3.5)^2$ $Σresidual^2=(7+1.75\times(-2)-3.5)^2+(6+1.75\times(-1)-3.5)^2+(3+1.75\times0-3.5)^2+(2+1.75\times1-3.5)^2+(0+1.75\times2-3.5)^2$ $Σresidual^2=0.875$