document.write( "Question 221567: the length of a rectangle is 12 meters longer than half the width. the area of the rectangle is 90 square meters. find the dimensions of the rectangle. \n" ); document.write( "
Algebra.Com's Answer #166147 by drj(1380)\"\" \"About 
You can put this solution on YOUR website!
The length of a rectangle is 12 meters longer than half the width. The area of the rectangle is 90 square meters. Find the dimensions of the rectangle.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Step 1. Let w be the width.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Step 2. Let \"w%2F2%2B12\" be the length.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Step 3. Area \"A=w%28w%2F2%2B12%29=90\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Step 4. Solving A in Step 3 yields the following steps.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"w%5E2%2F2+%2B12w=90\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Multiply 2 to both sides to get rid of denominator\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"2w%5E2%2F2%2B2%2A12w=90%2A2\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"w%5E2%2B24w=180\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Subtract 180 from both sides to get a quadratic equation\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"w%5E2%2B24w-180=180-180\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"w%5E2%2B24w-180=0\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Step 5. To solve equation in Step 5, use the quadratic formula given below\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\" \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "where a=1, b=24, and c=-180\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"aw%5E2%2Bbw%2Bc=0\" (in our case \"1w%5E2%2B24w%2B-180+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"w%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
\n" ); document.write( "
\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%2824%29%5E2-4%2A1%2A-180=1296\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=1296 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-24%2B-sqrt%28+1296+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"w%5B1%5D+=+%28-%2824%29%2Bsqrt%28+1296+%29%29%2F2%5C1+=+6\"
\n" ); document.write( " \"w%5B2%5D+=+%28-%2824%29-sqrt%28+1296+%29%29%2F2%5C1+=+-30\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"1w%5E2%2B24w%2B-180\" can be factored:
\n" ); document.write( " \"1w%5E2%2B24w%2B-180+=+1%28w-6%29%2A%28w--30%29\"
\n" ); document.write( " Again, the answer is: 6, -30.\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%2B24%2Ax%2B-180+%29\"

\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "With \"w=6\", then \"w%2F2%2B12=15\". Area A=6*15=90 which is a true statement.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Step 6. ANSWER: The dimensions of a rectangle are 6 meters and 15 meters.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "I hope the above steps were helpful.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Good luck in your studies!\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );