Graphs Of Circles

                     Lesson 1

                                                                                                                       

                                                             Problem:                   Write the equation of a circle that has a center at (-2, 4) and a radius of 2?

 

                                                             Solution                    The equation of a Circle is: (x - h)2 + (y - k)2 = r2;

 Step 1:                         where coordinate of the center of the circle is (h, k) and r is radius.                                               

                     

                                                                                 Solution                          The equation of given circle is [x - (-2)] 2 + (y - 4)2 = (2)2;

                                                             Step 2:                                                                             

                                                                                 

                                                                                 Solution                          (x +2)2 + (y - 4)2 = 4

                                                             Step 3:    

                                                                                                  

                                                            Solution                     The answer is:  (x +2)2 + (y - 4)2 = 4

 Step 4:                                                                      

 Complete                                                                   

                                                                                                                               

                                                             Try two practice problems:  

 

                                                                                               Do the following:

A.

Write the equation of a circle whose diameter is 16 and whose center is at (2, 8)? 

B.

What are the coordinates of the center of this circle?

(x + 5)2 + (y - 7)2 = 25.

 

                                                                                               

 

 

 

        

© Math Worksheets World.com