document.write( "Question 1014596: Solve:
\n" ); document.write( " x-6y-2z=-8
\n" ); document.write( "-x+5y+3z=2
\n" ); document.write( "3x-2y-4z=18
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Algebra.Com's Answer #630920 by addingup(3677)\"\" \"About 
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x-6y-2z=-8
\n" ); document.write( "-x+5y+3z=2
\n" ); document.write( "3x-2y-4z=18
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\n" ); document.write( "x-6y-2z=-8
\n" ); document.write( "-x+5y+3z=2
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\n" ); document.write( " -y+z= -6
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\n" ); document.write( "x-6y-2z=-8
\n" ); document.write( "3x-2y-4z=18
\n" ); document.write( "On the first equation multiply all terms by -3:
\n" ); document.write( "-3x+18y+6z= 24
\n" ); document.write( "Add the equations:
\n" ); document.write( "-3x+18y+6z= 24
\n" ); document.write( "3x-2y-4z= 18
\n" ); document.write( "---------------
\n" ); document.write( "16y+2z= 42
\n" ); document.write( "Now we have two new equations:
\n" ); document.write( "-y+z= -6
\n" ); document.write( "16y+2z= 42
\n" ); document.write( "Multiply the 1st equation times -2
\n" ); document.write( "2y-2z= 12
\n" ); document.write( "Add equations
\n" ); document.write( "16y+2z= 42
\n" ); document.write( "2y-2z= 12
\n" ); document.write( "18y= 54 Divide both sides by 18
\n" ); document.write( "y= 3 Now we know the value of y.
\n" ); document.write( "Take one of the last two equations and find z:
\n" ); document.write( "16y+2z= 42
\n" ); document.write( "16(3)+2z= 42
\n" ); document.write( "48+2z= 42
\n" ); document.write( "2z= -6
\n" ); document.write( "z= -3
\n" ); document.write( "You say, what if I chose the other equation to find z? Well:
\n" ); document.write( "2y-2z= 12
\n" ); document.write( "2(3)-2z= 12
\n" ); document.write( "6-2z= 12
\n" ); document.write( "-2z= 6
\n" ); document.write( "z= -3 Same answer. Cool, no?
\n" ); document.write( "Now we know y and z, let's go back to one of the original equations to find x:
\n" ); document.write( "x-6y-2z=-8
\n" ); document.write( "x-6(3)-2(-3)= -8
\n" ); document.write( "x-18+6= -8
\n" ); document.write( "x-12= -8
\n" ); document.write( "x= 4
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\n" ); document.write( "Am I right? Let's check:
\n" ); document.write( "x-6y-2z=-8; 4-6(3)-2(-3)= -8; 4-18+6= 8; -18+10= -8 Correct
\n" ); document.write( "-x+5y+3z=2; -4+5(3)+3(-3)= 2; -4+15-9= 2; 11-9= 2 correct
\n" ); document.write( "3x-2y-4z=18; 3(4)-2(3)-4(-3)= 18; 12-6+12= 18; 6+12= 18 Correct
\n" ); document.write( "We have the correct answers.
\n" ); document.write( "J\r
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