Answer:
125°
Explanation:
The angle marked f° is called an "external angle" of the triangle. Relative to that external angle, the two internal angles marked 44° and 81° are called "remote internal angles." Because f° and the adjacent internal angle are supplementary (add to 180°), and because all of the internal angles of the triangle add to 180°, the measure of f is equal to the sum of the remote interior angles:
f° = 44° + 81°
f° = 125°