document.write( "Question 553418: solve the system using either method of subsititution or elimination 3x+5y+4z=13,5x+2y+3z=-9,6x+3y+4z=-8 \n" ); document.write( "

Algebra.Com's Answer #360860 by mananth(16946) $\"\"$ $\"About$

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3x+5y+4z=13 --------------1
\n" ); document.write( "5x+2y+3z=-9 --------------2
\n" ); document.write( "6x+3y+ 4z=-8 --------------3
\n" ); document.write( "
\n" ); document.write( "consider equation 1 &2 Eliminate y
\n" ); document.write( "Multiply 1 by -2
\n" ); document.write( "Multiply 2 by 5
\n" ); document.write( "we get
\n" ); document.write( "-6x-10y-8z=-26
\n" ); document.write( "25x+10y+15z=-45
\n" ); document.write( "Add the two
\n" ); document.write( "19x+0y +7z=-71 -------------4
\n" ); document.write( "consider equation 2 & 3 Eliminate y
\n" ); document.write( "Multiply 2 by -3
\n" ); document.write( "Multiply 3 by 2
\n" ); document.write( "we get
\n" ); document.write( "-15x-6y -9z=27
\n" ); document.write( "12x+6y+ 8z=-8
\n" ); document.write( "Add the two
\n" ); document.write( "-3x+0y-1z=19 -------------5
\n" ); document.write( "Consider (4) & (5) Eliminate x
\n" ); document.write( "Multiply 4 by 3
\n" ); document.write( "Multiply (5) by 19
\n" ); document.write( "we get 2
\n" ); document.write( "57x+21z =-213
\n" ); document.write( "-57x-19z=361
\n" ); document.write( "Add the two
\n" ); document.write( "0x+2z=148
\n" ); document.write( "/ 2
\n" ); document.write( "z=74
\n" ); document.write( "
\n" ); document.write( "Plug the value of z in 5
\n" ); document.write( "-3x-74= 19
\n" ); document.write( "-3x=93
\n" ); document.write( "x=-31
\n" ); document.write( "plug value of x & z in 1
\n" ); document.write( "-93+5y+ 296=13
\n" ); document.write( "5y=93-296+13
\n" ); document.write( "y= -38
\n" ); document.write( " \n" ); document.write( "

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