The Energon Pub

Ok, I am stuck on this. We're just starting proofs in my geometry class and I have yet to learn my properties. The question asks:

If m<JUC = m<IUE then m<JUI = m<CUE. What property does the question depict?

I feel like a compete idiot for not knowing the answer to this... Help?

Can you flip it? I don't think all of us can read in reverse.

I've only had algebra, but I have had proving statements. So as far as I can tell you have these:

JUC versus IUE and JUI versus CUE. Unless I'm mistaken, those denote the angles in the figure. So let's substitute a bit:

JUC = 1 + 2
IUE = 2 + 3

JUI = 1
CUE = 3

Since it asks a property, whatever that is, I'm assuming it's asking for an equation for angle 2, or IUC.

Turns out it was the Angle Addition Postulate. Don't know how, since it was under the propeties section