Where find how to find the base of a triangle with the height and hypotenuse?
Instead, continue north. The first room on the east will have two chests in it and a Shrine of Air. Continue west from the Shrine of Fire. The corridor opens into a long room with six side rooms - three on each side. Clear out those fiind rooms and then procede to the doorway. This leads out to the central hub room, except that this time, you have control over the bridges.