The Triangle Angle Sum Theorem states that the sum of the interior angles of a triangle is always 180 degrees.
In your triangle, we have:
- Angle A = 103 degrees
- Angle D = 22 degrees (this is the angle at point D, which is adjacent to angle C)
- We need to find the measure of angle C.
To find angle C, we first need to calculate the sum of angles A and D:
\[ A + D = 103^\circ + 22^\circ = 125^\circ \]
Now, since the sum of all angles in a triangle is 180 degrees, we can find angle C by subtracting the sum of angles A and D from 180 degrees:
\[ C = 180^\circ - (A + D) = 180^\circ - 125^\circ = 55^\circ \]
Thus, the measure of angle C is 55 degrees.