Hello I am a sophmore and have only taken Algebra I and am now taking Algebra II, no geometry yet. One of the requirements to join Mu Alpha Theta is to have taken and/or be finishing algebra I&II and geometry. I was wondering if i take geometry online this year while I’m in algebra II, would I be eligable? Thank you for your feedback. 
You would be eligible, and you would also be in a very good place to compete for the Theta category. Your strong basis in Algebra 2 will prove very helpful. Good luck!