document.write( "Question 264711: solve by eilimination
\n" ); document.write( "1)3x+7y =48
\n" ); document.write( " 5x-7y= -32\r
\n" ); document.write( "\n" ); document.write( "2)-2x+3y =25
\n" ); document.write( " -2x+6y=58 \r
\n" ); document.write( "\n" ); document.write( "3)3x+8y = 81
\n" ); document.write( " 5x+6y=-39 \r
\n" ); document.write( "\n" ); document.write( "4)8x+13y=179
\n" ); document.write( " 2x-13y=-69 \n" ); document.write( "

Algebra.Com's Answer #194832 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "I'll just do the 3rd one, the hardest one:\r\n" );
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document.write( "To eliminate the x's:\r\n" );
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document.write( "The coefficients of x are 3 and 5.\r\n" );
document.write( "The least common multiple of 3 and 5 is 15. We want to\r\n" );
document.write( "make one of the coefficients of x 15 and the other one\r\n" );
document.write( "-15.  To do that we multiply the first equation through\r\n" );
document.write( "by 5 and the second one through by -3:\r\n" );
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document.write( "Add the two equations term by term\r\n" );
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document.write( "Go back to the original system:\r\n" );
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document.write( "To eliminate the y's:\r\n" );
document.write( "The coefficients of y are 8 and 6.\r\n" );
document.write( "The least common multiple of 8 and 6 is 24. We want to\r\n" );
document.write( "make one of the coefficients of y 24 and the other one\r\n" );
document.write( "-24.  To do that we multiply the first equation through\r\n" );
document.write( "by 3 and the second one through by -4:\r\n" );
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document.write( "Add the two equations term by term\r\n" );
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document.write( "Edwin

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