document.write( "Question 1142298: One of my math problems asks that you use Cramer's rule to solve this linear system.
\n" ); document.write( "5x+10y=70
\n" ); document.write( "5x+25z=270
\n" ); document.write( "10y+25z=300
\n" ); document.write( "When I put zeros on the third column to make it a 3x3 because it has to be the same I get 0. Please help me solve this problem \n" ); document.write( "
Algebra.Com's Answer #763009 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
use Cramer's rule to solve this linear system.\r\n" );
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document.write( "\"system%285x%2B10y=70%2C%0D%0A5x%2B25z=270%2C+%0D%0A10y%2B25z=300%0D%0A%0D%0A%29\"\r\n" );
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document.write( "Write it this way with 0 coefficients for the missing letters:\r\n" );
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document.write( "We begin by finding the determinant \"D\". It consists \r\n" );
document.write( "of just the three columns of x, y, and z coefficients,\r\n" );
document.write( "in that order, but does not contain the constants, the\r\n" );
document.write( "three numbers to the right of the equal signs.\r\n" );
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document.write( "\"D=abs%28matrix%283%2C3%2C5%2C10%2C0%2C5%2C0%2C25%2C0%2C10%2C25%29%29\".\r\n" );
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document.write( "It has value \"D=-2500\".\r\n" );
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document.write( "Next we find \"D%5Bx%5D\".\r\n" );
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document.write( "Dx has all the same elements as D except that the 1st column is replaced by\r\n" );
document.write( "the three numbers that occur after the equal signs in the system, in the\r\n" );
document.write( "order that they occur top to bottom:\r\n" );
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document.write( "\"D%5Bx%5D=abs%28matrix%283%2C3%2C70%2C10%2C0%2C270%2C0%2C25%2C300%2C10%2C25%29%29\".\r\n" );
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document.write( "It has value \"D%5Bx%5D=-10000\".\r\n" );
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document.write( "Next we find \"D%5By%5D\".\r\n" );
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document.write( "Dy has all the same elements as D except that the 2nd column is replaced by\r\n" );
document.write( "the three numbers that occur after the equal signs in the system, in the\r\n" );
document.write( "order that they occur top to bottom:\r\n" );
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document.write( "\"D%5By%5D=abs%28matrix%283%2C3%2C5%2C70%2C0%2C5%2C270%2C25%2C0%2C300%2C25%29%29\".\r\n" );
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document.write( "It has value \"D%5By%5D=-12500\".\r\n" );
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document.write( "Next we find \"D%5Bz%5D\".\r\n" );
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document.write( "Dz has all the same elements as D except that the 3rd column is replaced by\r\n" );
document.write( "the three numbers that occur after the equal signs in the system, in the\r\n" );
document.write( "order that they occur top to bottom:\r\n" );
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document.write( "\"D%5Bz%5D=abs%28matrix%283%2C3%2C5%2C10%2C70%2C5%2C0%2C270%2C0%2C10%2C300%29%29\"..\r\n" );
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document.write( "It has value \"D%5Bz%5D=-25000\".\r\n" );
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document.write( "The values for x, y, and z are:\r\n" );
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document.write( "If you don't know how to find the value of a 3×3 determinant,\r\n" );
document.write( "go here:\r\n" );
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document.write( "https://www.youtube.com/watch?v=V3e7m-qFDFU \r\n" );
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document.write( "Edwin
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