Delete AC and focus on the intersection of AB and BC. Keeping points B and C fixed, move point A to different locations and observe how ZABC changes. What must you do to increase or decrease m ABC ? What happens if you move point A

to a location directly on CB? What is mABC at this location? Explain

The image of the triangles are missing and so i have attached it.

Explained below.

Step-by-step explanation:

If we delete line AC in the diagram, we are left with line AB and BC.

Now, we are told to leave points B and C fixed.

Now, if we move Point A to different locations, ∠ ABC will increase or decrease depending on the new location that point A is put.

Lastly, if we move Point A to a point on line CB, it means ∠ABC = 0° because it isn't subtended at any angle at all.