Answer
$ŷ=121.6+0.000017x_1-2.49x_2$
Work Step by Step
In MINITAB, enter the MRI Count values in C1, the Gender values in C2 (0 for males 1 for females) and the IQ values in C3.
Select Stats -> Regression -> Regression -> Fit Regression Model
Enter C3 in "Responses" and C1 C2 in "Continuous Predictors"
The least-squares regression line will be shown in "Regression Equation", where C3 is $ŷ$ (IQ), C1 is $x_1$ (MRI Count) and C2 is x2 (Gender).
$ŷ=121.6+0.000017x_1-2.49x_2$
