document.write( "Question 892960: I need help!!!
\n" ); document.write( "Suppose that you need to fence a rectangular play area in your backyard for your child or pet. Further, suppose that you know the length must be 8 feet longer than the width. The back of your house will serve as one side of the fenced area. Note: The perimeter (distance around) of a general rectangle is P = 2L + 2W, and its area is A = L x W. In this situation, P = L + 2W. The value for the area is 4500.\r
\n" ); document.write( "\n" ); document.write( "2.Write the equation of the perimeter in terms of the length, L, only
\n" ); document.write( "P=2W+2L
\n" ); document.write( "Write the area equation in terms of the length, L, only.
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\n" ); document.write( "What can you observe about the characteristics of that quadratic area function? Will this quadratic function’s graph cross the horizontal axis? How do you know?\r
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\n" ); document.write( "\n" ); document.write( "Show all your work for finding both the length and the width of this rectangular fenced area.\r
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\n" ); document.write( "\n" ); document.write( "Show all your work for calculating the cost of the fence.\r
\n" ); document.write( "\n" ); document.write( "Show all your work for calculating the cost per square foot of the fenced area.)\r
\n" ); document.write( "\n" ); document.write( "What observations and conclusions can you make about the results of them?)
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Algebra.Com's Answer #540945 by josgarithmetic(39623)\"\" \"About 
You can put this solution on YOUR website!
w for width
\n" ); document.write( "L for length
\n" ); document.write( "A for area
\n" ); document.write( "A=4500
\n" ); document.write( "L=8+w
\n" ); document.write( "Using your choice of 1*L to serve as one side of the rectangle region to be fenced, you choose L+2w for the length of fencing to use, c.
\n" ); document.write( "c for length of fencing to use.\r
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\n" ); document.write( "\n" ); document.write( "Perimeter of the rectangle region is 2w+2L, but your length of fencing is c=L+2w.\r
\n" ); document.write( "\n" ); document.write( "\"A=wL\"
\n" ); document.write( "\"A=w%28w%2B8%29\"
\n" ); document.write( "\"w%5E2%2B8w=A\"
\n" ); document.write( "\"w%5E2%2B8w-A=0\"------ One unknown variable, w, and one known variable, A as a given constant.
\n" ); document.write( "You have the choice to substitute for A now and if factorable quadratic, then factor the quadratic expression to solve for w; or keep going in symbolic form and substitute for A later. Seeing so many different factorizations for 4500, my work will be done first in symbolic form.\r
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\n" ); document.write( "\n" ); document.write( "\"w=%28-8%2B-+sqrt%2864-4A%29%29%2F2\"
\n" ); document.write( "\"w=%28-8%2B2sqrt%2816-A%29%29%2F2\"------- The PLUS form will be what is needed
\n" ); document.write( "\"highlight_green%28w=-4%2Bsqrt%2816-A%29%29\"
\n" ); document.write( "\"w=-4%2Bsqrt%2816%2B4500%29\"
\n" ); document.write( "\"highlight%28w=-4%2Bsqrt%284516%29%29\", keeping like this for now.\r
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\n" ); document.write( "\n" ); document.write( "\"wL=4500\"
\n" ); document.write( "\"L=4500%2Fw\"
\n" ); document.write( "\"L=4500%2F%28-4%2Bsqrt%284516%29%29\"
\n" ); document.write( "If you rationalize the denominator and simplify (not showing those steps here),
\n" ); document.write( "\"highlight%28L=%284500%2B1125sqrt%284516%29%29%2F1133%29\"----not simplifiable further.\r
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\n" ); document.write( "\n" ); document.write( "The amount of fence material c=L+2w
\n" ); document.write( "\"highlight%28c=%284500%2B1125sqrt%284516%29%29%2F1133%29%2B2sqrt%284516%29-8%29\"
\n" ); document.write( "You can then compute this as a decimal approximation if needed.
\n" ); document.write( "You could also first compute L and w and then find the value for c.
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