Question

Resposta da conta x+y=9
2x-y=6

Answer 1

x=9-y

2(9-y)-y = 6

18-2y-y = 6

18-3y = 6

-3y = -12

3y = 12

y = 4

x+4 = 9

x = 9-4

x = 5

(x,y) = (5,4)