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    I've tried hard solving these all together but couldn't ......Anyone kind enought o give a go ....


    4-12 = 3a + 4 (a - b )
    0 = 4 (b - a ) +5b + 8(b- c)
    -4 = 8 (c - b) + 6 c




    Thank you very much.....
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    Have you tried expanding brackets and simplifying each equation first?
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    (Original post by face05)
    I've tried hard solving these all together but couldn't ......Anyone kind enought o give a go ....


    4-12 = 3a + 4 (a - b )
    0 = 4 (b - a ) +5b + 8(b- c)
    -4 = 8 (c - b) + 6 c


    Thank you very much.....
    -8=7a-4b
    0=17b-4a-8c
    -4=-8b+14c
    hope it helps dont really get what the question is???
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    eqn1: make a the subject.
    eqn3: make c the subject.
    Substitute these into eqn2, solve for b.
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    essentially you're being asked to find a value for a, b and c that satisfy all three equations.
    Do this by eliminating values by substitution (as vc94 suggests above)
 
 
 
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