A:Answer It will support the TV if you swing it all the way out, and it will fit in the corner, but it will not be a 45% angel. This mount extends about 17 inches, but the centerline of a 55" TV is about 25 inches (depending on the TV). To put the mount in the exact corner, you would need about 24 inches of extension. The only way to have the TV "fit" with this mount would be to mount the back plate 10 inches to 16 inches away from the corner on the wall so it will be "more tilted" in one direction in the corner. If you get it mounted just right, you may be able to get a 30% angle on one wall and 60% on the other.