Question

qual e a resposta ?

x+2y=7
x-2y=-5

Answer 1

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

x + 2y = 7
1 + 2y = 7
2y = 7 - 1
2y = 6
y = 6/2
y = 3

BONS ESTUDOS!

Answer 2

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

x + 2y = 7
1 + 2y = 7
2y = 7 - 1
2y = 6
y = 6/2
y = 3