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G.GCI.3 Constructing a Circumcenter


1) Use the POLYGON Toolbar Image tool to construct a triangle. 2) Use the PERPENDICULAR BISECTOR (PB) Toolbar Image tool to construct the PB's of this triangle's 3 sides. 3) Plot the intersection of these 3 perpendicular bisectors (circumcenter).


Construct a circle centered at the circumcenter that passes through any vertex of this triangle. Why does this circle pass through the other 2 vertices of this triangle?

When you're done (or if you're unsure of something), feel free to check by watching the quick silent screencast below the applet.

Quick (Silent) Demo