Respostas

  • Usuário do Brainly
2014-08-25T15:11:16-03:00
 \left \{ {{5x-y=10} \atop {x-y=26}} \right.

isolar x
x=26+y

substit/
5x-y=10
5(26+y)-y=10
130+5y-y=10
4y=10-130
4y=-120
y=-120÷4
y=-30

como x=26+y
x=26-30
x=-4

S={(-4,-30)}