document.write( "Question 77025: Mouse Pad. The area of a rectangular mouse pad is 480 sq centimeters. Its length is 16 centimeters shorter than twice its width. \r
\n" ); document.write( "\n" ); document.write( "What are the lengths and width of the mouse pad in centimeters.\r
\n" ); document.write( "\n" ); document.write( "I am having problems creating an equation for this to solve. we are doing factoring with standard form. I know the answer is 20 cm and 24 cm but what I have come up with is 2x(x-16)=480. I know that you have to get a 0 on the = side. Can you help me.
\n" ); document.write( "Kelly
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Algebra.Com's Answer #55181 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
if we let x=width, y=length we get\r
\n" ); document.write( "\n" ); document.write( "\"480=x%2Ay\"\r
\n" ); document.write( "\n" ); document.write( "where the length is \r
\n" ); document.write( "\n" ); document.write( "\"y=2x-16\"\r
\n" ); document.write( "\n" ); document.write( "\"480=x%2A%282x-16%29\" Substitute 2x-16 into y\r
\n" ); document.write( "\n" ); document.write( "\"480=2x%5E2-16x\" Distribute\r
\n" ); document.write( "\n" ); document.write( "\"0=2x%5E2-16x-480\" Subtract 480 from both sides\r
\n" ); document.write( "\n" ); document.write( "Now we use the quadratic formula to solve for x:\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-16x%2B-480+=+0\") has the following solutons:
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\n" ); document.write( " \"x%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=%28-16%29%5E2-4%2A2%2A-480=4096\".
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\n" ); document.write( " Discriminant d=4096 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--16%2B-sqrt%28+4096+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-16%29%2Bsqrt%28+4096+%29%29%2F2%5C2+=+20\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-16%29-sqrt%28+4096+%29%29%2F2%5C2+=+-12\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-16x%2B-480\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-16x%2B-480+=+2%28x-20%29%2A%28x--12%29\"
\n" ); document.write( " Again, the answer is: 20, -12.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-16%2Ax%2B-480+%29\"

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\n" ); document.write( "\n" ); document.write( "Since a negative width doesn't make any sense, our answer is 20. So our length is\r
\n" ); document.write( "\n" ); document.write( "\"y=2%2820%29-16\"
\n" ); document.write( "\"y=40-16\"
\n" ); document.write( "\"y=24\"\r
\n" ); document.write( "\n" ); document.write( "So our width is 20 and our length is 24.\r
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