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#1 2007-10-17 08:15:23
- b300y
- Member
- Registered: 2007-10-17
- Posts: 1
simultaneous equations
help
5x + 4y =22
x + 4y = 14
my anwsers are
x = 2
y = 3
are they right:P
and
x - 4y = 26
3x + 2y = 8
help i dont understand that one
is there a easy solution for working this out thanks 
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#2 2007-10-17 08:55:46
- luca-deltodesco
- Member
- Registered: 2006-05-05
- Posts: 1,470
Re: simultaneous equations
you are correct for first: for second add the second equation twice to the first i.e.
(x - 4y)+2(3x+2y) = 26+2×8
7x = 42
x = 6
6 - 4y = 26
4y = -20
y = -5
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