document.write( "Question 935949: Please help me write a system of 3 linear equations in 3 variables given the solution set (-2,3,4). Thank you in advance. \n" ); document.write( "
Algebra.Com's Answer #569339 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Just make up 9 numbers, positive or negative \r\n" );
document.write( "at random, and use them as coefficients for \r\n" );
document.write( "x, y and z.\r\n" );
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document.write( "I made up these 9 numbers, completely at random\r\n" );
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document.write( "2,-5,3,-3,4,-2,1,5,-4\r\n" );
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document.write( "and put them as coefficients of x,y, and z, like this:\r\n" );
document.write( "followed by an equal sign\r\n" );
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document.write( " 2x-5y+3z = \r\n" );
document.write( "-3x+4y-2z = \r\n" );
document.write( "  x+5y-4z = \r\n" );
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document.write( "Then I substituted x=-2,y=3,and z=4 in each one, like this:\r\n" );
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document.write( " 2(-2)-5(3)+3(4) = -4-15+12 = -7\r\n" );
document.write( "-3(-2)+4(3)-2(4) =  6+12-8  = 10\r\n" );
document.write( "  (-2)+5(3)-4(4) = -2+15-16 = -3 \r\n" );
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document.write( "Then I put those results after the equal signs,\r\n" );
document.write( "and got this system of 3 equations and 3 unknowns:\r\n" );
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document.write( " 2x-5y+3z = -7\r\n" );
document.write( "-3x+4y-2z = 10\r\n" );
document.write( "  x+5y-4z = -3\r\n" );
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document.write( "That system has the solution set (x,y,z) = (-2,3,4)\r\n" );
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document.write( "You can make up as many as you like.  This is\r\n" );
document.write( "how teachers and people who write math books \r\n" );
document.write( "make up problems for students to solve. \r\n" );
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document.write( "Edwin
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