Question

resposta dessa conta e a ultima
c)x-y=10
x+y=8
pfv respondem rapido obrigado

Answer 1

Olá,

x-y = 10
x+y = 8
---------
x+x-y+y = 10+8
2x+0 = 18
2x = 18
2x/2 = 18/2
x = 9

x+y = 8
y = 8-x
y = 8-9
y = -1

Resposta:

x = 9 e y = -1