document.write( "Question 227710: I can get the equation and solve this but i am unsure how to apply it to get the dimensions of the rectangle. The problem is this:
\n" ); document.write( "Find the dimensions of a rectangle whose width is 7 feet less than its length and whose area is 120 square feet.
\n" ); document.write( "I was able to get the formula but am unsure how to get the dimensions. \n" ); document.write( "
Algebra.Com's Answer #169177 by jsmallt9(3758)\"\" \"About 
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Let x = length of the rectangle.
\n" ); document.write( "Since the width is 7 feet less, the width would be:
\n" ); document.write( "x - 7
\n" ); document.write( "Area of all rectangles is length * width (A = l*w). Substituting our expressions and the value for the ares of this rectangle we get:
\n" ); document.write( "\"120+=+%28x%29%28x-7%29\"
\n" ); document.write( "Now we solve this. Start by simplifying it (with the Distributive Property):
\n" ); document.write( "\"120+=+x%5E2+-7x\"
\n" ); document.write( "Since this is a quadratic equation, get one side equal to zero (by subtracting 120 from each side):
\n" ); document.write( "\"0+=+x%5E2+-7x+-120\"
\n" ); document.write( "Now we can either factor this or use the quadratic formula:
\n" ); document.write( "\"0+=+%28x+-+15%29%28x%2B8%29\"
\n" ); document.write( "Now we use the Zero Product Property which tells us that this (or any) product can be zero only if one of the factors is zero. So:
\n" ); document.write( "\"x-15+=+0\" or \"x%2B8+=+0\"
\n" ); document.write( "Solving these we get:
\n" ); document.write( "\"x+=+15\" or \"x+=+-8\"
\n" ); document.write( "Since x represents the length of the rectangle we must reject the negative answer. So the only possible length is 15. And the width, which is x-7, is 8. \n" ); document.write( "
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