Area and Perimeter Formulas
Triangle
| Equilateral Triangle | Isosceles Triangle | Scalene Triangle |
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Square
Rectangle
Rhombus
Rhomboid
P = 2 · (a + b)
A = b · h
Area of Trapezoid
Area of a Regular Polygon
n is the number of sides
Polygon
The area is obtained by triangulating the polygon and adding the area of these triangles.
A = T1 + T2 + T3 + T4
Circle
Circular Sector
Circular Segment
The circular area of the segment AB = Area of the circular sector AOB - Area of triangle AOB
Lune of Hippocrates
Area of the lune = area of the semicircle − area of circular segment.
Circular Trapezoid
Area enclosed between Two Concentric Circles
