Perpendicular Bisector

• Is perpendicular to a leg of a triangle

• Passes through the midpoint of that leg

• Is equidistant from the endpoints of that leg

The Circumcenter

• the point where the perpendicular bisectors intersect

• is equidistant from each vertex

• the center of a circle that can be drawn around the triangle so each vertex lies on the circle

• is inside the triangle (acute), outside the triangle (obtuse), on triangle (right)

Angle Bisectors in triangles

• bisects one angle of a triangle

• any point on the angle bisector equidistant from two sides of the triangle (measuring perpendicularly)

The Incenter

• the point where the angle bisectors intersect

• is equidistant from each SIDE (measuring perpendicularly)

• the center of the biggest circle that can be drawn inside the circle

• is always INSIDE the circle