Weighted GPA and does it matter?

I am currently taking AP and IB courses and in Utah, they apparently DO NOT weight GPA’s (I honestly don’t know if this is true, but from what I have heard, Utah doesn’t weight GPA’s). If this happens to be true, what is the point for me to take IB and AP courses? Aside, from the accelerated learning, I don’t want my GPA to suffer drastically. (Right now I am at a 3.65, not too great if I want to get into a better school) Lastly, how are you able to calculate your weighted GPA, factoring honors, AP, and IB courses.
-Thanks

One of the things most colleges look at for admission is class rigor. If your school does not calculate a weighted GPA then You don’t have one to calculate. You just send your UW GPA.

You are looking at it wrong. Colleges look at gpa and rigor of coursework. It doesn’t matter if your school or college uses a weighted gpa or not, Your UW is not going to be compared to someone’s Wgpa anyway–they aren’t stupid. it is still very meaningful to take the hardest courses and have the most rigorous transcript because that is usually a very important factor in admissions.

Look at U of Utah CDS, section C7. Very important = rigor of coursework, gpa, test scores.
http://www.obia.utah.edu/ia/cds/2014-2015/CDS_2014-2015.pdf#page=7