How do i solve x^2 - 2x - 63 = 0 by completing the square? like they showed me how here but i'm not sure how this appiles if there's already a c and it doesn't factor into something that can be perfectly squared.

Maybe you can try graphing it if the graph does not have any x-intercepts than it has no real roots

Basically you add a square after the 2x and then another square by the 63. Then, you use (b/2)^2 to put the answer in the square. Take b which is -2 in this case and divide it by 2.  (-2/2= -1), then you square your answer (-1^2= 1). so after doing those calcualtions take the 1 that you got and put it in the first square. For the second square you will put the negative of that number which is -1. Then once you multiply the numbers by what is in the square you'll factor it and get your answer. This is really complicated and you may need to watch a video to get it.