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.
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document.write( "x+2y+z=2
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document.write( "2x+3y+3z=-3
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document.write( "2x+3y+2z=2 \n" );
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Algebra.Com's Answer #90956 by ankor@dixie-net.com(22740)![]() ![]() 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 \n" ); document.write( " \n" ); document.write( " |