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#1 2008-05-13 05:37:12
- bilat
- Member
- Registered: 2008-04-23
- Posts: 4
Help
Please answer these questions
). If a = b - c, then:
a) c = b - a
b) c = a + b
c) c = a - b
). If A = 3b - c2, find the value of A when b = 4 and c = 2
a) 30
b) 16
c) 8
Bila 
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#2 2008-05-13 07:01:43
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Help
For the first one, you need to get c on its own.
Here's a clue: Because a = b-c, that means that a + (c-a) = b-c + (c-a).
For the second one, just plug in the numbers you're given and work out the answer.
(It's slightly ambiguous what c2 means: c x 2 or c². Probably the second, since c x 2 would probably be written 2c, but in this case they're both the same anyway.)
Why did the vector cross the road?
It wanted to be normal.
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