Pete's QBASIC Site

So I am making a game and I need to figure out how to get my ball to bounce off the walls. My wall stops at 450 and I am in screen 9. Any help would be appreciated. I had bx = bx + 5 for the speed and had an if then statement. if bx <=450 then bx = bx - 5 and it stops the ball , but i can't quite fi...