Answer:
The marked angle GEF is 25
Step-by-step explanation:
Here, we want to calculate the value of the marked angle
Mathematically, a diagram should do justice to this
Please check the attachment for the diagram
The theorem we want to use is that the sum of opposite interior angles equals the exterior angle
Thus, mathematically;
2x + 1 + x + 19 = 6x + 2
3x + 20 = 6x + 2
6x-3x = 20-2
3x = 18
x = 18/3
x = 6
The angle marked GEF is x + 19
That will be 6 + 19 = 25
