# Geometry's Formulas

## Rhombus, regular polygon, ellipse, segment sphere, torus

### The Rhombus

The Rhombus is a special parallelogram, that
is parallelogram which has two consecutive sides congruent.

The Rhombus thus has all sides congruent and
diagonals perpendicular.

Also, the Rhombus area can be calculated using parallelogram formula.

### Regular Polygon

The Regular Polygon the convex polygon which has all sides congruent (equal).

For a regular polygon area is calculated by multiplying no. sides to the length of one of them.
Here we have a regular hexagon, so no. sides equals 6. So we perimeter
.
The area of a regular polygon calculated by the formula
, where P is the polygon's perimeter, and a is the apothem of the polygon (perpendicular to the center of a polygon on one of its sides).

### The Ellipse

The Ellipse  is defined as the flat curve which is the locus of points for which the sum of distances from two fixed points (called the focus of the ellipse) is constant.
Ellipse area is calculated as

.

### TheThorus

The Area of a Thorus  is calculated using the formula
.

## Other solids

### The Spheric Callote

The area of Spheric Callote could be calculated using the formula
.

### The Spheric Zone

The area of Spheric Zone could be calculated using the formula (the same as that of the Spheric Callote):
.

### The Single Base Spherical Segment

The Volume for the Single Base Segment Spherical is calculated using the formula:
.

### The Spherical Segment with two bases

The Volume for the Segment Spherical with two bases is calculated using the formula:
.

Keywords: geometry, mathematical formulas, geometric formulas, Diamonds, rhombus, regular polygon, ellipse, torus