Hello, @peterson, and welcome to the Processing Forum!
The text in your post is strangely formatted, making it difficult to read.
Also, when seeking help here, it is important to be specific regarding what you are trying to find out. For example, are you asking about calculating the area of a triangle, given the coordinates of its three vertices? If you clarify this, we may be able to help.
Which mode of Processing are you using? Is it Java, Python, or p5.js?
See Guidelines—Asking Questions for advice on asking questions on the Forum.