document.write( "Question 216320: the length of a rectangle Is 6 feet more than three times the width. the area of the rectanle is 240 square feet. what are the dimensions?  \n" ); document.write( "
Algebra.Com's Answer #163338 by drj(1380)\"\" \"About 
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The length of a rectangle is 6 feet more than three times the width. The area of the rectangle is 240 square feet. What are the dimensions? \r
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\n" ); document.write( "\n" ); document.write( "Step 1. Let w be the width and 3w+6 is the length since rectangle is 6 feet more than three times the width.\r
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\n" ); document.write( "\n" ); document.write( "Step 2. Area = width * length = w(3w+6) = 240 square feet\r
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\n" ); document.write( "\n" ); document.write( "Step 3. Then we can put the equation in Step 2 in quadratic form\r
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\n" ); document.write( "\n" ); document.write( "\"3w%5E2%2B6w=+240\"\r
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\n" ); document.write( "\n" ); document.write( "Subtract 240 to both sides of the equation\r
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\n" ); document.write( "\n" ); document.write( "\"3w%5E2%2B6w-240=0\"\r
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\n" ); document.write( "\n" ); document.write( "Step 4. We can use the quadratic formula given as\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r
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\n" ); document.write( "\n" ); document.write( "where a=3, b=6, and c=-240\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"aw%5E2%2Bbw%2Bc=0\" (in our case \"3w%5E2%2B6w%2B-240+=+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=%286%29%5E2-4%2A3%2A-240=2916\".
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\n" ); document.write( " Discriminant d=2916 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-6%2B-sqrt%28+2916+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"w%5B1%5D+=+%28-%286%29%2Bsqrt%28+2916+%29%29%2F2%5C3+=+8\"
\n" ); document.write( " \"w%5B2%5D+=+%28-%286%29-sqrt%28+2916+%29%29%2F2%5C3+=+-10\"
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\n" ); document.write( " Quadratic expression \"3w%5E2%2B6w%2B-240\" can be factored:
\n" ); document.write( " \"3w%5E2%2B6w%2B-240+=+3%28w-8%29%2A%28w--10%29\"
\n" ); document.write( " Again, the answer is: 8, -10.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B6%2Ax%2B-240+%29\"

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\n" ); document.write( "\n" ); document.write( "So select the positive solution for positive dimensions:\r
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\n" ); document.write( "\n" ); document.write( "\"w=8+\" and \"3w%2B6=3%2A8%2B6=30\"\r
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\n" ); document.write( "\n" ); document.write( "Verify area.... \"8%2A30=240\"...which is a true statement.\r
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\n" ); document.write( "\n" ); document.write( "Step 5. Dimensions of the rectangle are a width of 8 feet and a length of 30 feet.\r
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\n" ); document.write( "\n" ); document.write( "I hope the above steps were helpful.\r
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\n" ); document.write( "\n" ); document.write( "For FREE Step-By-Step videos in Introduction to Algebra, please visit \r
\n" ); document.write( "\n" ); document.write( "http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit \r
\n" ); document.write( "\n" ); document.write( "http://www.FreedomUniversity.TV/courses/Trigonometry.\r
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\n" ); document.write( "\n" ); document.write( "Good luck in your studies!\r
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\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
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