# Online Math Dictionary: H

Easy to understand math definitions for K-Algebra mathematics
Just scroll down or click on the word you want and I'll scroll down for you!

 hemisphere heptagon hexagon hexahedron horizontal hyperbola hypotenuse

 HemisphereA hemisphere is half of a sphere.   On our planet, the top half is called the Northern Hemisphere and the bottom half is called theSouthern Hemisphere.  HeptagonA heptagon is a seven sided polygon.   The heptagon in the picture on the right is a regular heptagon because all the sides and angles are the same (congruent). For more info on heptagons, check out my properties of heptagons page.  HexagonA hexagon is a six sided polygon.   The hexagon in the picture on the right is a regular hexagon because all the  sides and angles are the same (congruent). For more info on hexagons, check out my properties of hexagons page.  HexahedronA hexahedron is a six sided three dimensional geometric figure (a polyhedron).   A regular hexahedron is a cube because all the faces are the same size (congruent).  Horizontal
horizontal line is a line that runs along the horizon. HyperbolaHere's the official algebra definition:  A hyperbola is the intersection of a vertical plane with two inverted circular cones.  It is the set of points whose distances from two fixed points (the foci)  have  a constant distance. For more info, more pictures and an easier explanation of what a hyperbola really is, check out my Intro to Hyperbolas lesson.  HypotenuseThe hypotenuse of a right triangle is the side that is opposite the right (90 degree) angle. A B C D E F G H I no J's K L M N O P Q R S T U V W no X's no Y's no Z's