 # Equations of Circles: Finding the Equation of a Circle

##### This Equations of Circles: Finding the Equation of a Circle interactive also includes:

It's all about location and size. With the aid of the interactive, pupils explore the relationship between the location and size of a circle and its equation. The learners use that relationship to determine the equation of a circle given its center and radius and vice versa. Given an equation in standard form, users rewrite it in general form.

##### Instructional Ideas

• Working in pairs, have one classmate graph a circle and the other determine the equation of the circle, then write it both in standard and general form
##### Classroom Considerations

• Requires knowledge of squaring a binomial
• Individuals using the interactive must sign up for a free CK-12 account
##### Pros

• Includes feedback and hints for problems
• The additional material provides extra examples and a problem set
##### Cons

• Contains an incorrect coefficient answer in problem number three