Answer:
I have attached a screenshot (Please read explanation)
Explanation:
first, you must put you given into the two column proof
Since BC is a bisector, the angles are equal.
You would then need to add the two smaller angles together to get the larger one.
Substitute the measure of angle ABD (52)
Then, substitute ABC for CBD because they are equal.
Then just add them.
After adding, divide them (I couldn't fit this into the screenshot) to get ABC is 26 degrees.
Hope this helps :-)