## Question:

There is a system of equations:

```
x = a xor b;
y = b xor c;
```

if only x and y are known, is it possible to know b?

## Answer:

No. Due to the commutative property, we will always have two pairs. It's easy to check.

For x = 1, y = 0:

```
1 = 1 xor 0
0 = 0 xor 0
```

or

```
1 = 0 xor 1
0 = 1 xor 1
```

For x = 1, y = 1:

```
1 = 1 xor 0
1 = 0 xor 1
```

or

```
1 = 0 xor 1
1 = 1 xor 0
```

etc.