document.write( "Question 1151844: 2x + 6y + 3z = −16
\n" ); document.write( "5x − 3y − 5z = 71
\n" ); document.write( "4x + 3y + 2z = 10
\n" ); document.write( "This is my first question! Find, x,y,z. Make sure they are all true!!\r
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\n" ); document.write( "\n" ); document.write( "x + y + z = 4
\n" ); document.write( "x − y + z = 2
\n" ); document.write( "x − y − 2z = −1
\n" ); document.write( "This is my second question! Find, x,y,z. make sure they are all true!\r
\n" ); document.write( "\n" ); document.write( "Thank you to whoever answers this!
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Algebra.Com's Answer #773697 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
2x + 6y + 3z = −16
\n" ); document.write( "5x − 3y − 5z = 71
\n" ); document.write( "4x + 3y + 2z = 10
\n" ); document.write( "This is my first question! Find, x,y,z.
\n" ); document.write( "======================
\n" ); document.write( "I'll do this one. You then try the others and email via the TY note for help or to check your work.
\n" ); document.write( "-------
\n" ); document.write( "I'll use elimination.
\n" ); document.write( "Multiply the 2nd & 3rd eqns by 2 so all the y coefficients are the same.
\n" ); document.write( "----
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\r\n" );
document.write( "2x +  6y +  3z = −16\r\n" );
document.write( "10x − 6y − 10z = 142\r\n" );
document.write( " 8x + 6y +  4z = 20\r\n" );
document.write( "-----\r\n" );
document.write( "2x +  6y +  3z = −16\r\n" );
document.write( "10x − 6y − 10z = 142\r\n" );
document.write( "-------------------------------------- Add\r\n" );
document.write( "12x - 7z = 126\r\n" );
document.write( "---\r\n" );
document.write( "10x − 6y − 10z = 142\r\n" );
document.write( " 8x + 6y +  4z = 20\r\n" );
document.write( "------------------------------------- Add\r\n" );
document.write( "18x - 6z = 162\r\n" );
document.write( "Now there are 2 eqns in 2 variables, x & z\r\n" );
document.write( "---\r\n" );
document.write( "12x - 7z = 126 --- Eqn A\r\n" );
document.write( "18x - 6z = 162 --- Eqn B\r\n" );
document.write( "---\r\n" );
document.write( "Multiply Eqn A by 1.5 to make the x coeff's the same:\r\n" );
document.write( "18x - 10.5z = 189\r\n" );
document.write( "18x - 6z = 162 --- Eqn B\r\n" );
document.write( "------------------------------------------- Subtract\r\n" );
document.write( "-4.5z = 27\r\n" );
document.write( "-9z = 54\r\n" );
document.write( "z = -6\r\n" );
document.write( "===================================\r\n" );
document.write( "12x - 7z = 126 --- Eqn A\r\n" );
document.write( "Sub for z and find x:\r\n" );
document.write( "12x - 7*-6 = 126\r\n" );
document.write( "12x = 84\r\n" );
document.write( "x = 7\r\n" );
document.write( "=========================\r\n" );
document.write( "

\n" ); document.write( "Sub for x & z in any equation and find y.\r
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