Chapter 4 - Section 4.2 - Assess Your Understanding - Vocabulary and Skill Building - Page 215: 9g

$Σresidual^2=2.4$

Since $ŷ =2.2x+1.2$ $Σresidual^2=Σ(y_i-ŷ _i)^2=Σ[y_i-(2.2x_i+1.2)]^2=Σ(y_i-2.2x_i-1.2)^2$ $Σresidual^2=(-4-2.2\times(-2)-1.2)^2+(0-2.2\times(-1)-1.2)^2+(1-2.2\times0-1.2)^2+(4-2.2\times1-1.2)^2+(5-2.2\times2-1.2)^2$ $Σresidual^2=2.4$