Question

2x+y=1 x+3y=8 na subs

Answer 1

Olá,

2x + y = 1
x + 3y = 8

Isolando y:
y = 1 - 2x

Encontrando x:
x + 3y = 8
x + 3(1-2x) = 8
x + 3 - 6x = 8
3 - 5x = 8
-5x = 8 - 3
5x = -5
x = -1

Encontrando y:
y = 1 - 2x
y = 1 -2*(-1)
y = 1 + 2
y = 3

S = {(-1, 3)}

Bons estudos ;)