document.write( "Question 803306: I) An owner of a small business borrows money on three separate credit cards. X dollars on his Mastercard, y dollars on his Visa Card, z dollars on his American Express card. These amount satisfy the following equations.
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\n" ); document.write( "1.18x + 1.15y + 1.09z = 11,244.25
\n" ); document.write( "3.54x - .55y + .27z = 3,732.75
\n" ); document.write( ".06x + .05y + .03z = 414.75\r
\n" ); document.write( "\n" ); document.write( "How much money did the owner borrow on each card
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Algebra.Com's Answer #484280 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"1.18x+%2B+1.15y+%2B+1.09z+=+11244.25\"$ .......eq.1
\n" ); document.write( " $\"3.54x+-+.55y+%2B+.27z+=+3732.75\"$ .......eq.2
\n" ); document.write( " $\".06x+%2B+.05y+%2B+.03z+=+414.75\"$ .......eq.3........all equations multiply by $\"100\"$ to get whole numbers
\n" ); document.write( "___________________________________\r
\n" ); document.write( "\n" ); document.write( " $\"118x+%2B+115y+%2B+109z+=+1124425\"$ .......eq.1
\n" ); document.write( " $\"354x+-+55y+%2B+27z+=+373275\"$ .......eq.2
\n" ); document.write( " $\"6x+%2B+5y+%2B+3z+=+41475\"$ .......eq.3
\n" ); document.write( "_____________________________\r
\n" ); document.write( "\n" ); document.write( " $\"118x+%2B+115y+%2B+109z+=+1124425\"$ .......eq.1........multiply by $\"3\"$ then subtract eq.2 from eq.1
\n" ); document.write( " $\"354x+-+55y+%2B+27z+=+373275\"$ .......eq.2
\n" ); document.write( "______________________________\r
\n" ); document.write( "\n" ); document.write( " $\"354x+%2B+345y+%2B+327z+=+3373275\"$ .......eq.1
\n" ); document.write( "-
\n" ); document.write( " $\"354x+-+55y+%2B+27z+=+373275\"$ .......eq.2
\n" ); document.write( "_______________________________\r
\n" ); document.write( "\n" ); document.write( " $\"354x+-354x%2B+345y%2B+55y%2B+327z-+27z=+3373275-373275\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+400y%2B+300z=+3000000\"$ ........divide by $\"100\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4y%2B+3z=+30000\"$ .........solve for $\"y\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4y+=+30000-3z\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"y+=+30000%2F4-3z%2F4\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"y+=+7500-0.75z\"$ ....................eq.1a\r
\n" ); document.write( "\n" ); document.write( "go to
\n" ); document.write( " $\"6x+%2B+5y+%2B+3z+=+41475\"$ .......eq.3......plug in eq.1a\r
\n" ); document.write( "\n" ); document.write( " $\"6x+%2B+5%287500-0.75z%29+%2B+3z+=+41475\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"6x+%2B+37500-3.75z+%2B+3z+=+41475\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"6x+%2B+37500-0.75z++=+41475\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"6x+=+0.75z%2B41475-37500\"$ .......solve for $\"x\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"6x+=+0.75z%2B3975\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"x+=+0.75z%2F6%2B3975%2F6\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"x+=+0.125z%2B662.5\"$ ...............eq1b\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "go to $\"354x+-+55y+%2B+27z+=+373275\"$ .......eq.2......plug in eq.1a and eq.1b\r
\n" ); document.write( "\n" ); document.write( " $\"354%280.125z%2B662.5%29++-+55%287500-0.75z%29++%2B+27z+=+373275\"$ ............solve for $\"z\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"44.25z%2B234525-412500%2B41.25z%2B+27z+=+373275\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"44.25z%2B41.25z%2B+27z+=+373275-234525%2B412500\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"112.5z+=+551250\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"z+=+551250%2F112.5\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28z+=+4900%29\"$ ..........now find $\"x\"$ and $\"y\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"x+=+0.125z%2B662.5+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"x+=+0.125%2A4900%2B662.5\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"x+=+612.5%2B662.5+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28x+=+1275%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"y+=+7500-0.75z\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"y+=+7500-0.75%2A4900\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"y+=+7500-3675\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28y+=3825%29\"$ \r
\n" ); document.write( "\n" ); document.write( "so, he borrows
\n" ); document.write( " $\"highlight%28x+=+1275%29\"$ dollars on his Mastercard,
\n" ); document.write( " $\"highlight%28y+=3825%29\"$ dollars on his Visa Card,
\n" ); document.write( " $\"highlight%28z+=+4900%29\"$ dollars on his American Express card
\n" ); document.write( " \n" ); document.write( "

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