Solving the triangle requires solving all of the dimensions involve in the polygon given. We are given an angle, and two of the sides of the triangle. We can solve the third side by using the law of cosines.
b² = a²+c²-2accos(B)
b² = 38² + 18² - 2(38)(18)cos(36)
b = 25.7
We use the law of sines to solve for the angles.
a/sinA = b/sinB
38/sinA = 25.7/sin36
A = 60.4°
C = 180 - 36 - 60.4 = 83.6°