im positive you can use it, however its not gonna give you any advantage over any other calculator (unless your taking the SAT II math2c), the SAT I math section, is specifically designed to test your math abliites up to algebra (breifly touching on geometry). If you have a good foundation of algebra and are able to logically think through mathematics, you will do fine. I took the test numerous times and the lowest i ever got on SAT I math was a 740, ended up with a 790 though - although i double checked every answer and dont remember missing one - im sure that it was some stupid mistake, like not reading the questino right and giving X, instead of X+4. ETS tends to do that alot of the sats, they will give you some problem like (for the sake of making a point i will give an easy question) like X/4=16, and tell you to give 2X, however tons of people dont read the quesion right and give X because they feel panicked for time.
So my advice to you, stop worrying about which calculator to use, and concentrate, go slow enough to understand each question, but fast enough to finsih the secton within the time limit. I eneded each math section with usually 15 + minutes to spare, so you have plenty of time.
Now verbal... that is another thing....