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# 3 unknowns simultaneous equation in vectors watch

1. I have:

x = (2/3) * (b-a) + y
y = (1/3) * (2b-a) + z
z = (1/3) * (4b-3a) + x

I need to work out x, y and z in terms of a and b.
2. ordering the equations 1 to 3 from top to bottom, all you do is substitute 2 into 1, and then 3 into your new equation, leaving you with an equation in a,b and x. re-arrange to get your equation in the form x=f(a,b), substitute this into 3 to get z as a function of a and b, and finally substitute this new equation into 2.
3. (Original post by immense010)
ordering the equations 1 to 3 from top to bottom, all you do is substitute 2 into 1, and then 3 into your new equation, leaving you with an equation in a,b and x. re-arrange to get your equation in the form x=f(a,b), substitute this into 3 to get z as a function of a and b, and finally substitute this new equation into 2.
I get x = x when subbing 3 into new eq
4. In general (i.e. unless 4b=3a) there is no solution, so I wish you luck in expressing x, y or z in terms of a and b!

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