I think this problem is pictured very misleadingly and might even be incomplete.
Triangles ADB and DBC share the side DB. But the line CA does not actually exist as pictured, CA has to be in fact 2 segments that can’t meet in the middle, because of how these segments divide the angles at A and C (by 1/3 ratio and by half respectively).
But then you end up with 2 different triangles, one of them (ADB) iscosceles that have no real solution, unless we had more information relating them, like if AB and DC were parallel, but that is a stretch given the picture misleadingness.
You can see yourself that the middle segment has to be “hit” right in the middle on the right side, but has to be hit above the middle (dividing itself into 1/3 above and 2/3 below) from the left side.
Your drawing does not hold scrutiny!
Let me show you my skills in advance design software Paint
This doesn’t make sense
The segment on the left side will be colinear with the right side if there are x degrees above and 2x degrees below the line as in my drawing above.
ABD is 6x + Y, there fore A center line to B is also 4X
Whatever is on the other side of the horizontal line is 180-4X
A centerline D is 4X + (180-4X) therefore C centerline B is essentially the same put 3X by the B