The Washington Monument is an obelisk, a tall, thin, four-sided monument that tapers to a pyramidal top. Each face of the pyramidal
top of the Washington Monument is an isosceles triangle. The height
of each triangle is 55.5 feet, and the base of each triangle measures
34.4 feet. Find the length, to the nearest tenth of a foot, of one of the
two congruent legs of the triangle.
(please include HOW to get the answer, not just the answer)