Answer
$ŷ=35.83+4.80x_1-0.00394x_2-0.0658x_3$
Work Step by Step
In MINITAB, enter the Engine Size values in C1, the Curb Weight values in C2, the Horsepower values in C3 and the Miles per Gallon values in C4.
Select Stats -> Regression -> Regression -> Fit Regression Model
Enter C4 in "Responses" and C1 C2 C3 in "Continuous Predictors"
The least-squares regression line will be shown in "Regression Equation", where C4 is $ŷ$ (Miles per Gallon), C1 is $x_1$ (Engine Size), C2 is $x_2$ (Curb Weight) and C3 is $x_3$ (Horsepower).
$ŷ=35.83+4.80x_1-0.00394x_2-0.0658x_3$
