document.write( "Question 902943: A rectangle sign must have an area of 34 square yards. Its length must be 2 yards more than its width. Find the exact dimensions of the sign. \n" ); document.write( "
Algebra.Com's Answer #547747 by Stitch(470)\"\" \"About 
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Let L = length of the sign
\n" ); document.write( "Let W = width of the sign
\n" ); document.write( "Since you are given two unknowns, you will need two equations.
\n" ); document.write( "Area(A) of a rectangle = Length x Width
\n" ); document.write( "Equation 1: \"A+=+L+%2A+W\" (Equation for the area of a rectangle)
\n" ); document.write( "Equation 2: \"L+=+W+%2B+2\" (The length of the sign is 2yds more than the width)
\n" ); document.write( "Given: A = 34 yds^2
\n" ); document.write( "Plug 34 into equation 1 for A
\n" ); document.write( "Equation 1: \"A+=+L+%2A+W\"
\n" ); document.write( "\"34+=+L+%2A+W\"
\n" ); document.write( "Notice that equation 2 is already solved for L
\n" ); document.write( "Plug (W + 2) into equation 1 for L
\n" ); document.write( "\"34+=+%28W+%2B+2%29+%2A+W\"
\n" ); document.write( "Multiply the W through on the right hand side
\n" ); document.write( "\"34+=+W%5E2+%2B+2W\"
\n" ); document.write( "Subtract 34 from both sides
\n" ); document.write( "\"0+=+W%5E2+%2B+2W+-+34\"
\n" ); document.write( "Now you can use the quadratic equation to solve for W
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"aW%5E2%2BbW%2Bc=0\" (in our case \"1W%5E2%2B2W%2B-34+=+0\") has the following solutons:
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\n" ); document.write( " \"W%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%282%29%5E2-4%2A1%2A-34=140\".
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\n" ); document.write( " Discriminant d=140 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-2%2B-sqrt%28+140+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"W%5B1%5D+=+%28-%282%29%2Bsqrt%28+140+%29%29%2F2%5C1+=+4.91607978309962\"
\n" ); document.write( " \"W%5B2%5D+=+%28-%282%29-sqrt%28+140+%29%29%2F2%5C1+=+-6.91607978309962\"
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\n" ); document.write( " Quadratic expression \"1W%5E2%2B2W%2B-34\" can be factored:
\n" ); document.write( " \"1W%5E2%2B2W%2B-34+=+1%28W-4.91607978309962%29%2A%28W--6.91607978309962%29\"
\n" ); document.write( " Again, the answer is: 4.91607978309962, -6.91607978309962.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B2%2Ax%2B-34+%29\"

\n" ); document.write( "\n" ); document.write( "The quadratic equation tells us that W = 4.916 & -6.916
\n" ); document.write( "Since we can not have a negative distance we will only use W = 4.916
\n" ); document.write( "Now plug 4.916 into equation 2 for W
\n" ); document.write( "Equation 2: \"L+=+W+%2B+2\"
\n" ); document.write( "\"L+=+%284.916%29+%2B+2\"
\n" ); document.write( "\"highlight%28L+=+6.916%29\"
\n" ); document.write( "The Length of the lawn is 6.196 yards and the Width is 4.916 yards
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