# Circle Equations and Graphs Worksheets

You already know what a circle is. It is a shape easy to make and the distance between the center of a circle and its edges at all points is the same. Based on this idea the circle equation is formed. A circle equation is: x2 + y2 = radius2 The radius of a circle is always the same and if it isn’t, then it is not a circle. When you draw a circle on a graph paper, you first assume a point which is at a particular distance from the center. Let's consider the points are (0, 5). Hence, the value of the radius according to x2 + y2 = radius2 will be 0 + 25 = 25. Based on these values we can make other prediction regarding what values will make the square of radius equal to 25.

• ### Basic Lesson

Guides students through matching equation of a circle and graphs. As standard form equation of circle is:(x-h)2 +(y-k)2 = r2. Given the equation can be written as: (x - 0)2 + (y-0)2 = (2)2 here h=0,k=0 & r=2, and standard equation is x2 +y2 = (2)2.

• ### Intermediate Lesson

Demonstrates how to match equations of circles and visual graphs.

• ### Independent Practice 1

A really great activity for allowing students to understand the concepts of the Circle Equations and Graphs. Match the standard equations and graphs.

• ### Independent Practice 2

Students use Circle Equations and Graphs in 20 assorted problems. The answers can be found below.

• ### Homework Worksheet

Students are provided with 12 problems to achieve the concepts of Circle Equations and Graphs.

• ### Skill Quiz

This tests the students ability to understand Circle Equations and Graphs.