Question

{ x -y=50
{ X + y = 100
Método dá substituicao

Answer 1

x+y=100
x=100-y
x-y=50
100-y-y=50
2y=50-100
2y=-50
y=-50÷2
y=-25

x+y=100
x-25=100
x=100+25
x=125

Prova Real
125-25
100