document.write( "Question 89175: I would appreciate any help with this. I don't know how to isolate the variable or which equation to work with first...
\n" ); document.write( "Solve:
\n" ); document.write( "5x-2y+2z=-24
\n" ); document.write( "x-3y-4z=33
\n" ); document.write( "3x+3y-2z=7
\n" ); document.write( " \n" ); document.write( "
Algebra.Com's Answer #64980 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Solve:
\n" ); document.write( "5x - 2y + 2z = -24
\n" ); document.write( " x - 3y - 4z = 33
\n" ); document.write( "3x + 3y - 2z = 7
\n" ); document.write( ":
\n" ); document.write( "Perform elimination operations, adding or subtracting to get rid of one of the
\n" ); document.write( "variables. Do this twice and you have two, 2 unknown equation which are easy to deal with.
\n" ); document.write( ":
\n" ); document.write( "There are some obvious ways you can do this in this problem to eliminate z:
\n" ); document.write( "Multiply the 3rd equation by -1 and Add all three.
\n" ); document.write( "5x - 2y + 2z = -24
\n" ); document.write( " x - 3y - 4z = 33
\n" ); document.write( "-3x - 3y + 2z = -7
\n" ); document.write( "---------------------adding eliminates z
\n" ); document.write( "3x - 8y + 0z = 2
\n" ); document.write( ":
\n" ); document.write( "Add the first & third equations:
\n" ); document.write( "5x - 2y + 2z = -24
\n" ); document.write( "3x + 3y - 2z = 7
\n" ); document.write( "------------------adding eliminates z again
\n" ); document.write( "8x + 1y = -17
\n" ); document.write( ":
\n" ); document.write( "Our two, 2 unknown equations:
\n" ); document.write( "3x - 8y = +2
\n" ); document.write( "8x + 1y = -17
\n" ); document.write( ":
\n" ); document.write( "Multiply the 2nd equation by 8 and add it to the 1st:
\n" ); document.write( "64x + 8y = -136
\n" ); document.write( "3x - 8y = +2
\n" ); document.write( "----------------adding eliminates y, solve for x:
\n" ); document.write( "67x + 0x = -134
\n" ); document.write( "x = -134/67
\n" ); document.write( "x = -2
\n" ); document.write( ":
\n" ); document.write( "Find y using 8x +y = -17
\n" ); document.write( "8(-2) + y = -17
\n" ); document.write( "-16 + y = -17
\n" ); document.write( "y = -17 + 16
\n" ); document.write( "y = -1
\n" ); document.write( ":
\n" ); document.write( "I'll let you find out what z is. Check all three solution in the original equations \n" ); document.write( "
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