Respostas

2013-11-26T20:10:12-02:00
- 5x = 7y __ x= - 7y/5
1/3x - 4y = 2
1/3. -7y/5 - 4y = 2
-7y/15 - 4y = 2
-7y - 60 y = 30
-67y = 30
y = - 30/67

x = - 7 . - 30/67 : 5
x = 210/67 : 5
x = 42/67