Or go to the answers. Hexagon: A polygon with six angles and six sides. Semiannual - twice a year. Everything you need to prepare for an important exam!K-12 tests, GED math test, basic math tests, geometry tests, algebra tests. E For Equal. Today I have a set of letter H math activities to share! Addition, Subtraction, Multiplication, Division and Fraction Practice. Hyperboloid - a geometric solid whose equation is x2/a2+y2/b2-z2/c2=1 orx2/a2+y2/b2-z2/c2=-1. $ grep -F -w '