transfer GPA calculation?

I’m intending on applying to transfer from another state school to UT Austin for fall of 2020. I have a 4.0 at my currect college, but I took two dual enrollment courses through UT in high school and got a B+ in both of them. My current institution doesn’t have the +/- system like UT does, so when I apply, will they look at the GPA my institution calculated, or will they use their own system? I know that GPA is calculated by evaluating only transferable credit, but I would like to know this because it would make a difference in my confidence in my application.