Question

Qual o valor de z ?

x + y+ z = 0
2x - y - 2z = 1
6y + 3z = -12

Answer 1

x + y+ z = 0 ×(-2)

+↲

2x - y - 2z = 1

6y + 3z = -12

x+y+z=0

-3y-4z=1 ×(2)↲

6y+3z=-12

-5z=-10

z=-10/-5

z=2