document.write( "Question 1042297: Can I please have your assistance? What kind of system is 2x + y = 3, -6x - 3y = -9? \n" ); document.write( "
Algebra.Com's Answer #657281 by Edwin McCravy(20060)\"\" \"About 
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document.write( "2x + y = 3, -6x - 3y = -9?\r\n" );
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document.write( "It is a linear system of equations in 2 unknowns, x and y.\r\n" );
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document.write( "When we try to solve it,\r\n" );
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document.write( "we solve the 1st equation for y\r\n" );
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document.write( "2x + y = 3\r\n" );
document.write( "     y = 3 - 2x\r\n" );
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document.write( "Substitute in the 2nd equation:\r\n" );
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document.write( "-6x - 3(3 - 2x) = -9\r\n" );
document.write( "   -6x - 9 + 6x = -9\r\n" );
document.write( "             -9 = -9\r\n" );
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document.write( "The x's cancel.  When all the letters cancel\r\n" );
document.write( "out and we are left with a true equation,\r\n" );
document.write( "there are infinitely many solutions.\r\n" );
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document.write( "It is called a DEPENDENT system.\r\n" );
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document.write( "Edwin
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