# Circumcenter - 2019

Topic:
Geometry

## Follow the steps below to construct the circumcenter.

Use to construct the perpendicular bisector of segments AB, BC and AC. Use to add a point where the three perpendicular bisectors intersect. Use to label the point where the perpendicular bisectors intersect.

The point where all three perpendicular bisectors intersect is called the circumcenter. 1. Use to move point A, B or C so that the circumcenter is outside the triangle. What do you notice about the triangle?

Check all that apply

2. Use to move point C so that the circumcenter lies on a side of the triangle. What do you notice about the triangle?

Check all that apply

## We are now going to learn about the properties of a circumcenter.

Use to draw a segment from A to the circumcenter. Use to measure the length of the segment from A to the circumcenter. Repeat the process for vertex B and C Use to draw a circle with center at the circumcenter and through point A.

## Circumcenter Properties

3. Use to move point A, B or C around. What do you notice about the dashed segment lengths?

## The Circle

4. You constructed the circle to go through point A. When you move the triangle, you should notice that the circle also always goes through B and C. Why is that?

## Application for Circumcenter

5. For which of the following situations, would it make sense to find the circumcenter?

Check all that apply