Assuming this is for acadmic purposes, the memo you are writing may include information about the law (what EEOC laws require at state and federal levels) but it is about how that law will apply to your situation. So, at its basic form this is only an informational memorandum.
Memo formats are always the same:
MEMORANDUM (all capital letters, centered at the top of the page)
skip two lines at least after "MEMORANDUM"
FROM: skip one line in between each of these
Then begin to write the memo by discussing what the memo is talking about. For example, in your case, something like this would work: "Twenty (20) new employees must be hired for a new production line. This memorandum discusses the various state and federal Equal Employment Opportuntiy (EEO) laws which affect the advertising, hiring, and employment of employees to assure the company does not violate any of these laws."
Then you can discuss the actual laws: what they say, what they cover, what they require.
Then you can talk about your process for advertising the job; interviewing for the job; and selecting employees for the job will work to avoid any illegal discrimination.
That is about it.