Question

7x+y = 2x+6 (obs: "y" tem valor de 1)

Answer 1

7x+y = 2x+6
7x+1 = 2x+6
7x-2x=6-1
5x=5
x=5/5
x=1

Answer 2

7x+(1)=2x+6
5x=5
x=1
S={1}