document.write( "Question 138631: I am having trouble with my college homework sheets. Can someone please help me figure these out. I would really appreciate all the help you can give me. This problem is from homework sheet
\n" ); document.write( "16.) 6x-y-5z=27
\n" ); document.write( " -8x +2z=-56
\n" ); document.write( " 4y + z=8 \n" ); document.write( "
Algebra.Com's Answer #101208 by ankor@dixie-net.com(22740)\"\" \"About 
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16.) we can arrange it like this:
\n" ); document.write( " 6x - y - 5z = 27; eq:1
\n" ); document.write( "-8x + 0y +2z =-56; eq:2
\n" ); document.write( " 0x + 4y + z = 8: eq:3
\n" ); document.write( ":
\n" ); document.write( "Mult eq 3 by 5 and add it to eq1
\n" ); document.write( "6x - y - 5z = 27
\n" ); document.write( "0x +20y +5z = 40
\n" ); document.write( "--------------------adding eliminates z:
\n" ); document.write( "6x + 19y = 67
\n" ); document.write( ":
\n" ); document.write( "Mult eq 3 by 2 and subtract from eq2
\n" ); document.write( "-8x+ 0y + 2z = -56
\n" ); document.write( "0x + 8y + 2z = 16
\n" ); document.write( "--------------------Subtracting eliminates z again
\n" ); document.write( "-8x - 8y = -72
\n" ); document.write( "Divide equation by -8, resulting in
\n" ); document.write( "x + y = 9
\n" ); document.write( "y = (9-x); use for substitution in the equation: 6x + 19y = 47:\r
\n" ); document.write( "\n" ); document.write( "6x + 19(9-x) = 67
\n" ); document.write( "6x + 171 - 19x = 67
\n" ); document.write( "6x - 19x = 67 - 171
\n" ); document.write( "-13x = -104
\n" ); document.write( "x = \"%28-104%29%2F%28-13%29\"
\n" ); document.write( "x = +8
\n" ); document.write( ":
\n" ); document.write( "y = 9 -x
\n" ); document.write( "y = 9 - 8
\n" ); document.write( "y = +1
\n" ); document.write( ":
\n" ); document.write( "Use eq3 to find z, substitute for 1 for y:
\n" ); document.write( "4(1) + z = 8
\n" ); document.write( "z = 8 - 4
\n" ); document.write( "z = +4
\n" ); document.write( ":
\n" ); document.write( "Our solutions: x=8; y=1; z=4
\n" ); document.write( ":
\n" ); document.write( "Check solutions in eq1
\n" ); document.write( "6x - y - 5z = 27
\n" ); document.write( "6(8) - 1 - 5(4) =
\n" ); document.write( "48 - 1 - 20 = 47; confirms our solutions
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