Question

Se 1 0 1
2 1 x
0 1 2
= 0, então x é:
a) -5 b) -4 c) 3 d) 4 e) 5

Answer 1

| 1 0 1 | 1 0

| 2 1 x | 2 1

| 0 1 2 | 0 1

2 + 0 + 2 - (0 + x + 0) = 0

4 - x = 0

x = 4

Resposta: d) 4