Answer:
73
Explanation:
Note that 107 and x are supplementary angles. In other words, their sum is 180. Thus:

Subtract 107 from both sides:

So, the value of x is 73.
And we're done!
Notes:
x and z are vertical angles. Since x is 73, z must also be 73.
y and 107 are vertical angles. This means that y is also 107.