Answer:
No, triangles CDE and HGF are not necessarily congruent.
Explanation:
Notice that just having one angle equal in value doesn't make the triangles congruent. To start with, we know that the three internal angles of a triangle must add up to 180 degrees, but all we know when one is 50 degrees, the other two must add up to 130 degrees, which can be done by an infinite number of different angle combinations: 110 + 20, 90 + 40, 80 + 50, etc.