document.write( "Question 572708: The length of a rectangle is 5 inches longer than the width. The area of the rectangle is 50 inches squared. Find the length and the width of the rectangle. \n" ); document.write( "
Algebra.Com's Answer #368615 by mathsmiles(68)\"\" \"About 
You can put this solution on YOUR website!
First thing we want to do is write down what we know:\r
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\n" ); document.write( "\n" ); document.write( "Area of a rectangle:
\n" ); document.write( "A = L x W
\n" ); document.write( "L = 5 + W (length is 5 inches longer than the width)
\n" ); document.write( "A = 50 (Area is 50 inches squared)\r
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\n" ); document.write( "\n" ); document.write( "Putting this all together:
\n" ); document.write( "L x W = 50
\n" ); document.write( "Substituting for L with the above equation:
\n" ); document.write( "(5+W) x W = 50
\n" ); document.write( "Multiplying out the paren
\n" ); document.write( "5W + W^2 = 50
\n" ); document.write( "Subtract 50 from both sides and rearrange the terms a little:
\n" ); document.write( "W^2 + 5W - 50 = 0\r
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\n" ); document.write( "\n" ); document.write( "Now solve:
\n" ); document.write( "(W _ _) (W _ _) = 0 (we need to figure out the operand and the term for each)
\n" ); document.write( "The negative whole number indicates these have different signs
\n" ); document.write( "(W - _) (W + _) = 0
\n" ); document.write( "We need to find two factors of 50 whose difference (subtract them) gives 5.
\n" ); document.write( "50 = 25 x 2 Nope
\n" ); document.write( "50 = 5 x 10 Yup!\r
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\n" ); document.write( "\n" ); document.write( "Since the 5W term is positive, we need to put the 10 in the positive factor and 5 in the negative factor so ...
\n" ); document.write( "(W - 5)(W + 10) = 0
\n" ); document.write( "W -5 = 0
\n" ); document.write( "W = 5
\n" ); document.write( "W + 10 = 0
\n" ); document.write( "W = -10\r
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\n" ); document.write( "\n" ); document.write( "Since we're talking about the area of a rectangle, we have to assume it has positive sides or we've just entered another dimension. :-) So,
\n" ); document.write( "W = 5 inches
\n" ); document.write( "L = 5 + 5 (5 inches longer than the width)
\n" ); document.write( "L = 10 inches\r
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\n" ); document.write( "\n" ); document.write( "Checking:
\n" ); document.write( "A = L x W
\n" ); document.write( "A = 5 x 10
\n" ); document.write( "50 = 50 Correct!
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