problem with fillet command

Howdy! I'm working on drawing up an automotive poly-vee pulley and need to modify sharp corners to radii. No matter how many times I try this, it never gives me an option to change the radius size, nor does it actually change a sharp corner to a radius. Instead, depending on which order I select the lines, it rotates the second(in order of selection) line to another point. It appears the base point of rotation is the sharp corner that I'm trying to modify.

I've used quite a few CAD and CAD/CAM packages before without this being an issue, so I'm not sure what's going on.

I drew a small red box on the toolbar to set radius.

Your toolbar layout could be different, but try to find it in the toolbar area.

Thanks! I knew I was missing something and didn't see anything about that in the tutorial. I just wasn't 2% smarter than the device I was trying to operate.