Min Max Problems: You have something you want to minimize or maximize and you have a constraint. The widows have h, height, and w, width
Minimize wood usage U = 2h + 3w (note the change from perimeter - a typical problem)
The area is the constraint: A = 6 = hw
Solve the constraint for one variable and substitute into the function to minimize.
Take the 1st derivative of the now one-dependent variable function and equate to 0 to find critical points for the dependent variable.
You can check 2nd derivative to show that it's a min (second derivative >0) or you can plug into the derivative to show that it goes from - to + around critical point.
