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You can put this solution on YOUR website!
I'm not sure how to do this problem at all in my algebra class with solving the system of equations.
\n" ); document.write( "3x +14z = 80
\n" ); document.write( " y-7z =-30
\n" ); document.write( " x-2y =12
\n" ); document.write( "The solution is (__,__,__)
\n" ); document.write( "Please help with this problem\r
\n" ); document.write( "\n" ); document.write( "lets try to make this as easy as possible so you can do the same thing with other problems of this nature:
\n" ); document.write( "line all the coefficients on the variables up and the 3 solutions as well like so:
\n" ); document.write( "And we are going to use elimination...
\n" ); document.write( "Elimination means in this case to use a process of multiplication and addition to try to isolate variables and solve for them easier...
\n" ); document.write( " 3x + 0y + 14z = 80
\n" ); document.write( " 0x + y - 7z = -30 (multiply by 2)
\n" ); document.write( " x - 2y + 0z = 12
\n" ); document.write( "to get
\n" ); document.write( " 3x + 0y + 14z = 80
\n" ); document.write( " 0x + 2y - 14z = -60 (add to top row)
\n" ); document.write( " x - 2y + 0z = 12
\n" ); document.write( "to get
\n" ); document.write( " 3x + 2y + 0z = 20
\n" ); document.write( " 0x + 2y - 14z = -60
\n" ); document.write( " x - 2y + 0z = 12 (add to top row)
\n" ); document.write( "to get
\n" ); document.write( " 4x + 0y + 0z = 32
\n" ); document.write( " 0x + 2y - 14z = -60
\n" ); document.write( " x - 2y + 0z = 12
\n" ); document.write( "now you got
\n" ); document.write( " 4x = 32 so x = 8 (one variable solved and one row cleared)
\n" ); document.write( "plug in
\n" ); document.write( " 0x + 2y - 14z = -60 --> 2y - 14z = -60
\n" ); document.write( " 8 - 2y + 0z = 12 --> -2y + 0z = 4
\n" ); document.write( "now you got
\n" ); document.write( " -2y = 4 so y = -2 (another variable solved and another row cleared)
\n" ); document.write( "plug in
\n" ); document.write( " -4 - 14z = -60 --> -14z = -56
\n" ); document.write( "so z = 4 (last variable solved)
\n" ); document.write( "check:
\n" ); document.write( " 3(8) + 0(-2) + 14(4) = 80 --> 24 + 56 = 80 yes
\n" ); document.write( " 0(8) + (-2) - 7(4) = -30 --> -2 - 28 = -30 yes
\n" ); document.write( " (8) - 2(-2) + 0(4) = 12 --> 8 + 4 = 12 yes\r
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