Q4, W7: May 11-15 Geometry

TeacherKristin Andreason
Subject AreaGeometry Honors
Grade Level8
Week #May 11-15
Unit of InstructionUnit 8: Circles with & without Coordinates
Standard(s) Taught

MAFS.912.G-GPE.1.1:  Derive the equation of a circle of given center and radius using the Pythagorean Theorem; complete the square to find the center and radius of a circle given by an equation.

Learning Targets and Learning Criteria
  • identify the center and radius of a circle given its equation.
  • draw a right triangle with a horizontal leg, a vertical leg, and the radius of a circle as its hypotenuse
  • write the equation of a circle by using the distance formula (Pythagorean Theorem), the coordinates of a circle’s center, and the circle’s radius.
  • rewrite an equation of a circle in general (quadratic) form to standard form by completing the square.
Classroom Activities


  • Today you are going to watch a Zoom recorded video I made on deriving The Equation of a Circle.  In the video, I do a discovery lab.  I have attached the discovery lab in a Gradebook assignment called Equations of Circles.  I recommend that you print it out and do it along with the video!  Here is the link for the video:  



  • Please watch another Zoom video–Equations and Graphs (this one is short and shows examples of the two IXL’s you will be doing!  Here is the link for the video:


  • Then do IXL’s V.3 and V.7 in which you will be writing an equation from a graph and then graphing a circle from an equation.  If you watch the short video, they should be easy!


  • Please watch another short Zoom video–Equations and Properties (it will show you how to do the IXL).  Here is the link:


  • Then do IXL V.4


  • Today you are only watching a video–it is 36 minutes long and it is super important!  In this video (Converting to Standard Form), I will be teaching you how to convert the equation of a circle from general form to standard form by completing the square.  Then tomorrow you will do one more IXL on that skill.  You will not be able to do the IXL without this teaching!  Here is the link:



  • Please do IXL V.5 Convert Equations of Circles from General to Standard Form.


Assignments Due
  • IXL V.3
  • IXL V.7
  • IXL V.4
  • IXL V.5
Additional Resources