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**aband** I am stuck. I am working on some math homework and one of the problems is this:

Norman window has 48ft perimeter. Objective: determine the dimensions, h and r, that will allow the **max **amount of light to enter the window.

a) express the outer perimeter of the window in terms of r and h:

*so far I have *

*p=48ft*

*48=2r+2h+(pie)r*

*Now what?*

nothing ... you've answered part (a)

b)using a value of 48 feet for the outer perimeter, determine h in terms of r:

*what?!*

solve for h in the equation you found in part (a)

c)express the total area of the window, A, in terms of h and r:

A = 2rh + (pi r^2)/2

d)express the total area of the window, A, in terms of r only and simplify. (should be a quadratic function)

substitute what you found for h in part (b) into the area equation.

e) determine exact value of r that maximizes window:

find the vertex of the quadratic function