Do isosceles triangles always have two equal angles?

An isosceles triangle therefore has both two equal sides and two equal angles. The name derives from the Greek iso (same) and skelos (leg). A triangle with all sides equal is called an equilateral triangle, and a triangle with no sides equal is called a scalene triangle.

How do you prove an isosceles triangle with two equal angles?

If the triangles are congruent, then all their angles must be equal, and thus the angles opposite the equal sides must be equal. Therefore all isosceles triangles have two equal sides and two equal angles opposite the equal sides.

What are the two equal angles in an isosceles triangle called?

Terminology. In an isosceles triangle, the two equal sides are called legs, and the remaining side is called the base. The angle opposite the base is called the vertex angle, and the point associated with that angle is called the apex. The two equal angles are called the isosceles angles.

Can a triangle have 2 equal angles and not be isosceles?

If a triangle has two angles equal to each other, the sides which subtend the equal angles will also be equal to one another. Hence, by definition, such a triangle will be isosceles.

What triangle has no equal angles?

scalene triangle
Scalene. A scalene triangle has three different angles and none of its sides are equal in length.

What is the rule of isosceles triangle?

The rule for an isosceles triangle is that the triangle must have two sides of equal length. These two sides are called the legs of the triangle and the unequal side is called the base. The isosceles triangle theorem further states that the angles opposite to each of the equal sides must also be equal.

What do you call a polygon with 7 sides?

A heptagon is a seven-sided polygon. It is also sometimes called a septagon, though this usage mixes a Latin prefix sept- (derived from septua-, meaning “seven”) with the Greek suffix -gon (from gonia, meaning “angle”), and is therefore not recommended.

What are the angles in a isosceles triangle?

An isosceles triangle is a type of triangle that has two sides that are the same length. The two marked sides are both the same length. The two angles opposite these two marked sides are also the same: both angles are 70°. All three interior angles add to 180° because it is a triangle.

https://www.youtube.com/watch?v=fTP-F0YarGM