To find the volume, we need the height of the entire pyramid, not the
slant height of the lateral faces. If the slant height is the
hypotenuse, the bottom leg is 10 meters and the Pythagorean theorem will
give us the rest.
a2 + b2 = c2 (10 m)2 + h2 = (14.14 m)2 h = 10 m
Armed with the height, we're fully equipped to calculate the volume of this pyramidal puppy.