document.write( "Question 509441: a rectangle has a perimeter of 400 feet... express its area in terms of one of its sides,x \n" ); document.write( "
Algebra.Com's Answer #341455 by richard1234(7193)\"\" \"About 
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If x is the side length, then the other length is 200-x (not 400-x, see why?). The area would be x(200-x), or -x^2 + 200x. \n" ); document.write( "
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