From Latin: aequus -"equal" , angulum -"corner"
which has all three interior angles equal (congruent).
Drag the orange dots on each vertex
to reshape the triangle.
Notice it always remains an equiangular triangle. The angles A,B and C always remain equal in measure.
An equiangular triangle is a triangle where all three
are equal in measure.
Because the interior angles of any triangle always add up to 180°,
each angle is always a third of that, or 60°
The sides of an equiangular triangle are all the same length (congruent), and so an equiangular triangle is really
the same thing as an equilateral triangle. See Equilateral Triangles.
- All three sides of an equiangular triangle are congruent (same length).
- The area of an equiangular triangle can be calculated in the
but in this special case of an equilateral triangle, it is also given by the formula:
where S is the length of any one side.
- For an equiangular triangle, the radius of the
incircle is exactly half the radius of the
Constructing an Equiangular Triangle
It is possible to construct an equiangular triangle of a given side length using just a compass and straightedge.
This uses the same method as for an equilateral triangle, see
Constructing an Equilateral Triangle
Related triangle topics
Perimeter / Area
Congruence and Similarity
Triangle quizzes and exercises
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