If a girl says "I'll think about it" after being asked out?

im 21 she is 22, we see each other very rarely so we talk on Facebook and whatnot. I have asked her out once a long time ago, yes through Facebook. This first time she said we should get to know each other so OK. Well I asked her again about a year later just a bit ago, yes through Facebook again lol. She said she will think about it, so I see her in a few weeks, should I just ask her in person? is she waiting for me to just ask her in person or it this a total waste of time? Any opinions would be greatly appreciated :) thanks!
If a girl says "I'll think about it" after being asked out?
Post Opinion