Formulas from Geometry

 

Plane figures - perimeter (P), circumference (C), and area (A):

 

 

Rectangle

 

P = 2 l + 2 w

A = l w

 

 

Parallelogram

 

 

A = b h

 

 

Trapezoid

 

 

A =  ½ (a + b) h

 

 

Triangle

 

 

A = ½ b h

 

 

Circle

 

C = 2 π r

A = π r 2

 

 

 

Solid figures - surface area (S) and volume (V):

 

 

Rectangular Solid

 

S = 2 w l + 2 h l + 2 w h

V = l w h

 

 

Circular Cylinder

 

S = 2 π r 2 + 2 π r h

V = π r 2 h

 

 

Circular Cone

 

S = π r 2 + π r √(r 2 + h 2)

V = 1/3 π r 2 h

 

 

Sphere

 

S = 4 π r 2

V = 4/3 π r 3

 

 

 

 

 

The Pythagorean Theorem

 

 

Right Triangle

 

c 2 = a 2 + b 2