Hy everyone. First, Im sorry if I missed subforum. Please help me about this problem of least squares method. I solved first part of problem when you have to do least square method, but I dont understand how to put triangle in that coordinate system and calculate area of it. my online calculation of l.s.m is here ->

http://i46.tinypic.com/okvssn.jpg
Problem -> With the method of least squares find best line f(x) which goes through six given points from A to F. Calculate area of triangle bounded with that line, and axis X and Y.

Points are : A ( 18.6 , -143.8 ) ; B ( 29.5 , -250.2 ) ; C (32.5 , -278.3 ) ; D ( 41.5 , -365.8 ) ; E ( 54.5 , -490.9 ) ; F ( 62.9 , -575.5 )