Question

x-y=5 // 2x+3y=16 substituição

Answer 1

x= 5+y

2x+3y=16
2.(5+y) +3y=16
10 +2y +3y =16
10+5y=16
5y=16-10
5y=6
y=6/5

x= 5+y
x=5+6/5
x= 25+6/5
x=31/5

S={31/5, 6/5}