In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data:
diagram
Step 02:
angles (values x and y):
we must analyze the diagram to find the solution.
x = 81
5y - 39 = 180 - x
5y - 39 = 180 - 81
5y - 39 = 99
5y = 99 + 39
5y = 138
y = 138 / 5
The answer is:
x = 81
y = 138 / 5 = 27.6