Free Math Help
Free Math Help: Completing the Square in Circle Equations
This discussion examines how to complete the square in circle equations. Students learn about the math concept through definitions and examples with detailed solutions.
Integrated Publishing
Integrated Publishing: The Wheel & Axle
A solid chapter explanation of the wheel & axle simple machine. Examples, the basic math, explanation of mechanical advantage, drawings, solved problem. Use the Next button. There are four pages in this chapter.
University of Cambridge
University of Cambridge: Nrich: The Pi Are Square
Use the formula given for the area of a circle and a square to solve this challenge. This one page website has the solution available for you.
Purple Math
Purplemath: Geometry Word Problems: Introduction
Introduces how to set up and solve simple geometric-figure word problems. Includes advice regarding formulas to memorize.
ClassFlow
Class Flow: Goats and Monsters
[Free Registration/Login Required] Students explore methods to measure lengths of squares and radius of a circle in trying to keep a goat from escaping.
Rice University
Rice University: Cynthia Lanius: Circles Around Pythagoras
This site from the Rice University includes a fill-in-the-blank lesson on the definition of circles, as Pythagoras described.
Calculator Soup
Calculator Soup: Circle Calculator
Use this circle calculator to find the area, circumference, radius, or diameter of a circle. Given any one variable A, C, r or d of a circle you can calculate the other three unknowns.
Math Open Reference
Math Open Reference: Sector
Learn about sectors with this handy reference guide. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.
Homeschool Math
Homeschool Math: Circles
Lesson presents definitions of terms associated with circles and helps students learn to use a compass to draw circles and simple circle designs.
Mocomi & Anibrain Digital Technologies
Mocomi: What Is Circle?
Discusses the radius, diameter, circumference, and area of a circle.
Math Words
Math words.com: Radius of a Circle or Sphere
This site from MathWords.com explains and shows visually what the radius of a sphere is.