

Incenter of a Triangle
Geometry construction using a compass and straightedge
This page shows how to construct (draw) the incenter of a triangle with compass and straightedge or ruler.
The
Incenter of a triangle
is the point where all three
angle bisectors
always intersect, and is the center of the triangle's
incircle.
See Constructing the incircle of a triangle.
In this construction, we only use two bisectors, as this is sufficient to define the point where they
intersect,
and we bisect the angles using the method described in
Bisecting an Angle. The point where the bisectors cross is the incenter.
Printable stepbystep instructions
The above animation is available as a
printable stepbystep instruction sheet, which can be used for making handouts
or when a computer is not available.
Proof
The image below is the final drawing from the above animation.
 Q.E.D
Try it yourself
Click here for a printable incenter worksheet containing two problems to try.
When you get to the page, use the browser print command to print as many as you wish. The printed output is not copyright.
Other constructions pages on this site
Lines
Angles
Triangles
Right triangles
Triangle Centers
Circles, Arcs and Ellipses
Polygons
NonEuclidean constructions
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