Question

* + Y =11 rescreva os sistemass de equaçoes polininomiais do 1 grau

* -Y = 3

Answer 1

Bom dia! 

$\left \{ {{x+y=11} \atop {x-y= 3}} \right. \\ \\ \left \{ {{y=11-x} \atop {x-y= 3}} \right. \\ \\ x-y= 3 \\ \\ x-(11-x)= 3 \\ \\ x-11+x= 3 \\ \\ 2x= 3+11 \\ \\ x= \frac{14}{2}\to \boxed{x= 7} \\ \\ y= 11-x\to y = 11-7\to \boxed{y= 4}$