College Math
posted by Richard D .
Find the area of a rectangle if three of its corners are (3.7, 3.1), (1.2, 3.1), and
(1.2, 5.3). Hint: find the 4th corner first.

done , look back before reposting
Richard, you are asking a lot of unrelated question without showing any effort on your part
This is called "homework  dumping"
Exactly where are you having difficulties?