I’m having a problem with my home theater setup. Take a look at this picture and solve the problem below. (It is not neccessary to show your work, but I give bonus points for the least amount of work I have to do double-checking your results.)

John’s rear surround-sound pictures, which are mounted to the ceiling, are oriented so that sound from the tweeters delivers almost directly to the ears of his listeners (the black arrow) thereby ruining the intended effect of sound coming from behind. At what angle (xº) would John have to insert a wedge so that sound from the tweeters would be reflected off the wall (the blue arrow) to simulate the intended effect?

—Keep in mind that the measurements noted are to the existing tweeter which will move when the wedge is inserted!—