## MP5 – The Center of the Circle

15 Sep

How do you give students the opportunity to practice “I can use appropriate tools strategically”? How would your students find the center of a circle?

Every year, I am amazed at the connections students make between properties of circles that we have explored and what the center of the circle has to do with those properties.

We started on paper.

Some students moved their thoughts to technology.

Whose work would you select for an individual and/or whole class discussion?

Could we use the tangents to a circle from a point to find the center of the circle? Could we use the intersection of the angle bisectors of an equilateral triangle inscribed in a circle to find the center of the circle? Could we use the perpendicular bisector of a chord of a circle to find the center of the circle? Could we use the intersection of the perpendicular bisectors of a pentagon circumscribed about a circle to find the center of the circle? Could we use the intersection of the perpendicular bisectors of several chords of a circle to find the center of the circle? Could we use a right triangle inscribed in a circle to find the center of the circle? And so the journey continues …