Respostas

2014-03-31T20:01:30-03:00
|1 -2| = 1 - (0) = 1
|0  1|

|4  2| = 0 - (-2) = 2
|-1 0|

2x - y = 1 --> (.2) --> 4x - 2y = 2

3x + 2y = 2

soma as duas :

7x = 4

x = 4/7

agora o y :

3x + 2y = 2
3 . (4/7) + 2y = 2
12/7 + 2y = 2
12 + 14y = 14
14y = 2
y = 2/14
y = 1/7

y = 1/7
x = 4/7

1 4 1