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July 24, 2014

July 24, 2014

Posted by **sridhar** on Sunday, September 13, 2009 at 2:57pm.

- algebra 1 -
**Damon**, Sunday, September 13, 2009 at 4:42pmarea = A = L * B where L is length and B is width

Say back wall is one length

then

30 = L + 2B

or

L = 30 - 2 B

then

A = (30-2B)* B

A = -2B^2 + 30 B

That is a downward opening parabola (sheds water)

We want the axis of symmetry which contains the vertex which is at the top (maximum A)

So complete the square

B^2 -15 B = - A/2

B^2 - 15 B + 225/4 = -A/2 + 225/4

(B-15/2)(B-15/2) = -A/2 + 225/2

B = 15/2 = 7.5 feet

L = 30 - 2(7.5) = 15 feet

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