Question

Given the image, if AB is a semicircle and DB = 70 degrees, what is the measure of ACD?

Answer 1

I’m guessing that when you said DB, you meant DCB=70 degrees.
Continuing from there, since it’s a semi circle, the total angle is 180 degrees. Therefore, ACD = (180 - 70)degrees.
Answer => 110 degrees


Hint - Look at the semi circle as a protractor. It’s exactly like that. If one side is 70, then the other is 110.