Answer:
x = 115°
Explanation:
The sum of the 3 angles in a triangle = 180°, thus
To find the third angle in the triangle subtract the sum of the 2 given angles from 180, that is
∠BEC = 180° - (90 + 25)° = 180° - 115° = 65°
Now
∠DEB and ∠BEC form a straight angle and are supplementary, hence
x = ∠DEB = 180° - 65° = 115°