document.write( "Question 262852: im having a hard time with this problem,please help! if the length of a rectangular parking lot is 20 meters less than twice its width,and the perimeter is 800 meters,find the length of the parking lot. \n" ); document.write( "

Algebra.Com's Answer #193623 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"j\"$ = the length in meters
\n" ); document.write( "Let $\"k\"$ = the width in meters
\n" ); document.write( "Let $\"p\"$ = perimeter in meters
\n" ); document.write( "given:
\n" ); document.write( " $\"j+=+2k+-+20\"$ m
\n" ); document.write( " $\"p+=+800\"$ m
\n" ); document.write( "-------------------
\n" ); document.write( "The problem is to find $\"j\"$
\n" ); document.write( "The formula for the perimeter of a rectangle is:
\n" ); document.write( " $\"p+=+2j+%2B+2k\"$
\n" ); document.write( " $\"800+=+2j+%2B+2k\"$
\n" ); document.write( "Substitute the given value for $\"j\"$ in this equation
\n" ); document.write( " $\"800+=+2%2A%282k+-+20%29+%2B+2k\"$
\n" ); document.write( " $\"800+=+4k+-+40+%2B+2k\"$
\n" ); document.write( " $\"6k+=+840\"$
\n" ); document.write( " $\"k+=+140\"$ m
\n" ); document.write( "Now substitute this value in given equation
\n" ); document.write( " $\"j+=+2%2A140+-+20\"$
\n" ); document.write( " $\"j+=+280+-+20\"$
\n" ); document.write( " $\"j+=+260\"$
\n" ); document.write( "The length of the parking lot is 260 m
\n" ); document.write( "check answer:
\n" ); document.write( " $\"800+=+2j+%2B+2k\"$
\n" ); document.write( " $\"800+=+2%2A260+%2B+2%2A140\"$
\n" ); document.write( " $\"800+=+520+%2B+280\"$
\n" ); document.write( " $\"800+=+800\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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