document.write( "Question 123991: I have to solve each system by the addition method, and if a unique solution does not exist, state whether the system is inconsistent or dependent. I have no clue how to do these and I am hoping someone will help me.
\n" ); document.write( "x+2y+z=2
\n" ); document.write( "2x+3y+3z=-3
\n" ); document.write( "2x+3y+2z=2
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Algebra.Com's Answer #90956 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
x + 2y + z = 2
\n" ); document.write( "2x+ 3y +3z =-3
\n" ); document.write( "2x+ 3y +2z = 2
\n" ); document.write( ":
\n" ); document.write( "notice if you multiply the 2nd equation by -1, & add it to the 3rd equation
\n" ); document.write( ":
\n" ); document.write( "-2x - 3y -3z =+3
\n" ); document.write( "2x + 3y +2z = 2
\n" ); document.write( "------------------ adding eliminates both x & y, leaving us z
\n" ); document.write( "0x + 0y - 1z = 5
\n" ); document.write( "-z = 5
\n" ); document.write( "therefore
\n" ); document.write( "z = -5
\n" ); document.write( ":
\n" ); document.write( "Substitute -5 for z in the 1st equation
\n" ); document.write( "x + 2y - 5 = 2
\n" ); document.write( "x + 2y = 2 + 5
\n" ); document.write( "x + 2y = 7
\n" ); document.write( ":
\n" ); document.write( "Substitute -5 for z in the 2nd equation
\n" ); document.write( "2x + 3y + 3(-5) = -3
\n" ); document.write( "2x + 3y - 15 = -3
\n" ); document.write( "2x + 3y = -3 + 15
\n" ); document.write( "2x + 3y = +12
\n" ); document.write( ":
\n" ); document.write( "Now we can deal with 2 unknown equations to find x * y
\n" ); document.write( "Multiply eq: x +2y = 7 by -2 and add it to the above equation:
\n" ); document.write( "-2x -4y = -14
\n" ); document.write( " 2x +3y = +12
\n" ); document.write( "---------------- adding eliminates x, find y
\n" ); document.write( "0x - 1y = -2
\n" ); document.write( "y = +2
\n" ); document.write( ":
\n" ); document.write( "Find x using the 2nd equation, substitute for y and z:
\n" ); document.write( "2x + 3y +3z =-3
\n" ); document.write( "2x+ 3(2) + 3(-5) = -3
\n" ); document.write( "2x + 6 - 15 = -3
\n" ); document.write( "2x - 9 = -3
\n" ); document.write( "2x = -3 + 9
\n" ); document.write( "2x = 6
\n" ); document.write( "x = +3
\n" ); document.write( ":
\n" ); document.write( "Check solution in the 3rd equation
\n" ); document.write( "2x+ 3y +2z = 2
\n" ); document.write( "2(3) + 3(2) +2(-5) =
\n" ); document.write( "6 + 6 - 10 = 2
\n" ); document.write( ":
\n" ); document.write( "Therefore we can say this system is dependent on:
\n" ); document.write( "x = 3
\n" ); document.write( "y = 2
\n" ); document.write( "z = -5
\n" ); document.write( ":
\n" ); document.write( "I know there are a lot steps, but none of them are complicated, try to study
\n" ); document.write( "the procedure until it makes sense. A
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