Answer:
[tex]m<CAD=100[/tex]
Step-by-step explanation:
Triangle A B C extended to both sides from corners A and B. D is a point closer to point A . Angle C is located on the top of the triangle.
The diagram is attached below
In a triangle , external angle = sum of two opposite interior angles
so [tex]m<CAD=m<C +m<CBA[/tex]
[tex]m<CAD= 80 + 20=100[/tex]