In geometry, an equilateral triangle is a triangle in which all three sides are equal,
In the familiar Euclidean geometry, an equilateral triangle is also equiangular; that is.
All three internal angles are also congruent to each other and are each 60°.
An isosceles triangle is a triangle with (at least) two equal sides. In the figure below,
the two equal sides have length b and the remaining side has length a
Scalene triangle are triangles with three sides of different lengths. The math term for sides of different triangles is noncongruent sides.
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