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# 3 Simultaneous equations watch

1. 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.....
2. Have you tried expanding brackets and simplifying each equation first?
3. (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???
4. eqn1: make a the subject.
eqn3: make c the subject.
Substitute these into eqn2, solve for b.
5. 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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