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isosceles triangle∗
drini†
2013-03-21 12:22:02
An isosceles triangle is a triangle with two congruent sides. The angles
opposite these two sides are the base angles and the angle between those sides
is the vertex angle of the triangle.
This definition implies that any equilateral triangle is isosceles too, but there
are isosceles triangles that are not equilateral.
In any isosceles triangle, the angles opposite to the congruent sides are also
congruent. In fact, this condition could be used to give an alternate definition
of isosceles, since a triangle is isosceles if and only if it has two congruent angles.
In an equilateral triangle, the height, the median and the bisector to the
third side are the same line.
∗ hIsoscelesTrianglei created: h2013-03-21i by: hdrinii version: h30149i Privacy setting:
h1i hDefinitioni h51-00i h49J20i h49J30i h49-01i
† This text is available under the Creative Commons Attribution/Share-Alike License 3.0.
You can reuse this document or portions thereof only if you do so under terms that are
compatible with the CC-BY-SA license.
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