Thanks Narenn, this looks pretty good.
If I can offer one quick piece of advice about coordinate geometry: About half the time it breaks down into Pythagoras on a right-angle triangle, so always keep that in mind when looking at these questions. There aren't too many coordinate geometry questions on the GMAT but you may as well get them all right
Hope this helps!
Thanks Ron. I agree with your opinion.
In fact while going thru these concepts, i realized that substantial part of these concepts is based on Pythagorean theorem on right triangle e.g. distance formulae, slope, intercepts of a line, and all that. so in order to perform well in coordinate geometry it is helpful to think from this perspective.