How to enter negative numbers in Ti89 Titanium?? This is so hard. I wonder whether I need more training in Google search or is it that the Ti89Titanium has a very very poor Knowledge Base and Tutorial. How do you enter a negative value? During my search, I noticed that the Ti89 uses a key labelled (-) to enter a negative value, as opposed to -, the normal minus sign. I don't see this enigmatic (-) key on my Titanium. I removed the batteries, and it wasn't underneath neither. I Googled for the Titanium photo, just to ensure that my calculator did not have a severe casing defect. Everything seems normal. The (-) key does not exist on the Titanium. Trying to enter - simply ,then typing a number, and finally 'Enter', produces a Syntax error. On home, pressing the - button shows ans(1)-, which is not what I want. How do I enter the negative sign directly??