document.write( "Question 897155: An appartment building contains 12 units consisting of one bedroom and two bedroom apartments that rent for 360 and 450 per month when all units are rented the total is 4950 what is the number of two bedroom apartments \n" ); document.write( "

Algebra.Com's Answer #544009 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+a+\"$ = number of 1 br apts
\n" ); document.write( "Let $\"+b+\"$ = number of 2 br apts
\n" ); document.write( "-----------------------------
\n" ); document.write( "(1) $\"+a+%2B+b+=+12+\"$
\n" ); document.write( "(2) $\"+360a+%2B+450b+=+4950+\"$
\n" ); document.write( "---------------------------
\n" ); document.write( "(2) $\"+12a+%2B+15b+=+165+\"$
\n" ); document.write( "Multiply both sides of (1) by $\"+12+\"$
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "(2) $\"+12a+%2B+15b+=+165+\"$
\n" ); document.write( "(1) $\"+-12a+-+12b+=+-144+\"$
\n" ); document.write( "-------------------------
\n" ); document.write( " $\"+3b+=+21+\"$
\n" ); document.write( " $\"+b+=+7+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+a+%2B+b+=+12+\"$
\n" ); document.write( "(1) $\"+a+%2B+7+=+12+\"$
\n" ); document.write( "(1) $\"+a+=+5+\"$
\n" ); document.write( "The number of 2 br apts is 7
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+360%2A5+%2B+450%2A7+=+4950+\"$
\n" ); document.write( "(2) $\"+1800+%2B+3150+=+4950+\"$
\n" ); document.write( "(2) $\"+4950+=+4950+\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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