We can break the triangle into smaller and bigger triangles.
For the smaller triangle, we can get the length of the base using the tan ratio:

From the image, we have:

Therefore, we have:

For the bigger triangle, the base can be calculated using the same tan ratio but with the following parameters:

Therefore, we have:

From the image, we have that:

Therefore, we can solve for x as shown below:

The value of x is 156.15 units.