document.write( "Question 420741: Please help me solve this equation\r
\n" ); document.write( "\n" ); document.write( "4x + 4y + z = 2
\n" ); document.write( "-x + 2y + 3z = 5
\n" ); document.write( "x + y + 4z = -7 \n" ); document.write( "
Algebra.Com's Answer #293896 by mananth(16946)\"\" \"About 
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4x+4y+1z = 2-------------- 1
\n" ); document.write( "-1x +2y+3z =5-------------- 2
\n" ); document.write( "1x+ 1y +4z=-7--------------3
\n" ); document.write( "
\n" ); document.write( " consider equation 1 &2
\n" ); document.write( " Multiply 1 by 1
\n" ); document.write( " Multiply 2 by -2
\n" ); document.write( " we get
\n" ); document.write( " 4 x + 4 y + 1 z = 2
\n" ); document.write( " 2 x + -4 y + -6 z = -10
\n" ); document.write( " Add the two
\n" ); document.write( " 6 x + 0 y + -5 z = -8 ------------- 4
\n" ); document.write( " consider equation 2 & 3
\n" ); document.write( " Multiply 2 by 1
\n" ); document.write( " Multiply 3 by -2
\n" ); document.write( " we get
\n" ); document.write( " -1 x + 2 y + 3 z = 5
\n" ); document.write( " -2 x + -2 y + -8 z = 14
\n" ); document.write( " Add the two
\n" ); document.write( " -3 x + 0 y + -5 z = 19 ------------- 5
\n" ); document.write( " Consider (4) & (5)
\n" ); document.write( " Multiply 4 by 1
\n" ); document.write( " Multiply (5) by 2
\n" ); document.write( " we get
\n" ); document.write( " 6 x + -5 z = -8
\n" ); document.write( " -6 x + -10 z = 38
\n" ); document.write( " Add the two
\n" ); document.write( " 0 x + -15 z = 30
\n" ); document.write( " / -15
\n" ); document.write( " z = -2
\n" ); document.write( "
\n" ); document.write( " Plug the value of z in 5
\n" ); document.write( " -3 x + 10 = 19
\n" ); document.write( " -3 x = 9
\n" ); document.write( " x = -3
\n" ); document.write( " plug value of x & z in 1
\n" ); document.write( " -12 + 4 y + -2 = 2
\n" ); document.write( " 4 y = 12 + 2 + 2
\n" ); document.write( " 4 y = 16
\n" ); document.write( " y= 4
\n" ); document.write( " \n" ); document.write( "
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