



 
Kylie, I can help get you started. I drew a diagram, labeled the width of the rectangle w, the height h and the radius of the semicircle r, all in feet.
From the diagram w = 2r. Again from the diagram the perimeter is half the circumference of a circle of radius r plus the height of the rectangle twice plus the width of the rectangle once. You know the perimeter is 15 feet so
Again using the diagram write an expression for the area of the window. Use w = 2r to write this expression as a function of r and h and then use the perimeter expression to write the area as a function of r alone. Now use the calculus you know to maximize this function. Harley  


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