There are many basic concepts from Geometry that are used in Algebra, Trigonometry, and Calculus. Here are some simple formulas for commonly seen flat shapes:
Triangle  three sides  A = ½ bh  A = area, b = base, h = height 
Parallelogram  four sides, opposite sides are parallel  A = bh  A = area, b = base, h = height 
Trapezoid  four sides, top and base are parallel  A = ½(a+b)h  A = area, a = top, b = base, h = height 
Circle  all points the same distance from the center  A = πr^{2 }C = 2πr  A = area, r = radius C = circumference 
Three dimensional shapes are used all the time in practical applications. The abbreviations used for these formulas are:
S = surface area  V = volume  B = area of base (use formulas above) 
h = height  r = radius  s = distance tip to base on a cone 
Instead of area, with solids you want to find the surface area S and the volume V of the object.
Any Cylinder or Prism  parallel bases  V = Bh  
Right Circular Cylinder  base and sides form a right angle  V = πr^{2}h S = 2πrh 

Any Cone or Pyramid  any shape base 


Right Circular Cone  point to center point of base forms a right angle 


Sphere  all points the same distance from the center 

Geometry Book  Geometry published by Glencoe/McGraw Hill, copyright 2005
Postulates, Theorems, and Corollaries  a complete list of all postulates, theorems, and corollaries to theorems presented in the book begins on page R1 (after page 810) and it has purple edges to its pages.
Important vocabulary  in the book important words are highlighted in yellow. You should write these down in your Notables book or on a Foldable. An English and Spanish glossary starts on page R9 that gives definitions and a reference back to a page in the book. The Glossary has purple edges on its pages. Many of the glossary words from your book are also listed here.
Student Handbook  beginning on page 727 with green edges on its pages, this provides a good review of things you should have learned in math before beginning Geometry. There is an excellent review of graphing and basic Algebra.
Selected Answers – beginning on page R29 also has green edges on its pages. This section provides answers to odd problems for exercises, practice quizes, and the chapter reviews. Use these to check your own work to make sure you understand how to do the assignments.
Buttons created at ButtonGenerator.com.