Of course you can. If you're a high school junior or
senior, think about how you would have done on the test as an 8th
grader. You would have done much worse.
Over the years you've developed your vocabulary, your
ability to read and your ability to reason quantitatively. These are
skills you can always work on. We look at the SAT as an academic
fitness test; if you train for it, you can improve.