document.write( "Question 915411: Hi. This is the problem I have:\r
\n" ); document.write( "\n" ); document.write( "The length of a rectangle is 3 times its width. If its perimeter is 32m, what is its area?\r
\n" ); document.write( "\n" ); document.write( "My friend has only written down on my book:
\n" ); document.write( "3x4=12
\n" ); document.write( "12+12+4+4=32 and
\n" ); document.write( "12x4=48\r
\n" ); document.write( "\n" ); document.write( "I don't understand how she got these numbers and would like you to explain this to me.
\n" ); document.write( "Thank you.
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Algebra.Com's Answer #555565 by josgarithmetic(39626)\"\" \"About 
You can put this solution on YOUR website!
w for width, L for length;\r
\n" ); document.write( "\n" ); document.write( "L=3w;
\n" ); document.write( "and
\n" ); document.write( "2w+2L=32;
\n" ); document.write( "and you want to know area, which is wL.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Substitute for L in 2w+2L=32.
\n" ); document.write( "\"2w%2B2%283w%29=32\"
\n" ); document.write( "\"w%2B3w=16\"
\n" ); document.write( "\"4w=16\"
\n" ); document.write( "\"w=16%2F4\"
\n" ); document.write( "\"w=4\"
\n" ); document.write( "Use the now found value for w to compute or evaluate L.
\n" ); document.write( "\"L=3w\"
\n" ); document.write( "\"L=3%2A4\"
\n" ); document.write( "\"L=12\"
\n" ); document.write( "-
\n" ); document.write( "You now know both w=4 and L=12, and you can compute the area, w*L.
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