Answer:
The answer to the question provided is -70.
Without the screenshot, it's fairly difficult to know what your teacher wants exactly. I found this similar problem
brainly.com/question/13583475
which might help. It sounds like you have 4 semicircles which can be thought of as a division problem 12/3 = 4. Note how I'm dividing by 3 which is the width of each section (eg: from 6 to 9 is 9-6 = 3 units)
