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The point where the three "altitudes" of a triangle meet. An "altitude" is a line that goes through a vertex (corner point) and is at right angles to the opposite side. Try moving the points below, and notice: • theorthocenter can be inside or outside of the triangle.

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A set of lines or curves are said to be concurrent if they all intersect. at the same point. In the figure below, the three lines are concurrent because they all intersect at a single point P. The point P is called the "point of concurrency".

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X. One of several centers the triangle can have, thecircumcenter is the point where the perpendicular bisectors of a triangle intersect. The circumcenter is also the center of the triangle's circumcircle - the circle that passes through all three of the triangle's vertices.

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The formal name for the property of equality that allows one to add the same quantity to both sides of an equation. This, along with the multiplicative property of equality, is one of the most commonly used properties for solving equations.

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The Centroid is a point of concurrency of the triangle. It is the point where all 3 medians intersect and is often described as the triangle's center of gravity or as the barycent. Properties of the Centroid. It is formed by the intersection of the medians. It is one of the points of concurrency of a triangle.

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The exterior angle theorem is Proposition 1.16 in Euclid's Elements, which states that the measure of anexterior angle of a triangle is greater than either of the measures of the remote interior angles. This is a fundamental result in absolute geometry because its proof does not depend upon the parallel postulate.

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A midsegment is the line segment connecting the midpoints of two sides of a triangle. Since a triangle has three sides, each triangle has three midsegments. A triangle midsegment is parallel to the third side of the triangle and is half of the length of the third side.

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In geometry, an altitude of a triangle is a line segment through a vertex and perpendicular to (i.e., forming a right angle with) a line containing the base (the side opposite the vertex). This line containing the opposite side is called the extended base of the altitude.

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From Latin: vertex "highest point" Definition: The common endpoint of two or more rays or line segments. Vertex typically means a corner or a point where lines meet. For example a square has four corners, each is called a vertex. The plural form ofvertex is vertices.

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In geometry, a median of a triangle is a line segment joining a vertex to the midpoint of the opposing side, bisecting it. Every triangle has exactly three medians, one from each vertex, and they all intersect each other at thetriangle's centroid.

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There is a special triangle called an isosceles triangle. ... The easiest way to define an isosceles triangle is that it has two equal sides. In an isosceles triangle, we have two sides called the legs and a third side called the base. The angle located opposite the base is called the vertex.

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noun, Geometry. an angle formed between parallel lines by a third line that intersects them. 2. an angleformed within a polygon by two adjacent sides. Origin of interior angle.

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Two angles and included side (ASA) Definition: Triangles are congruent if any two angles and their included side are equal in both triangles. There are five ways to test that two triangles are congruent. This is one of them (ASA).

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Three sides equal (SSS)Definition: Triangles are congruent if all three sides in one triangle are congruent to the corresponding sides in the other. There are five ways to test that two triangles are congruent.

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Two angles and an opposite side (AAS) Definition: Triangles are congruent if two pairs of corresponding angles and a pair of opposite sides are equal in both triangles. There are five ways to test that two triangles are congruent.

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Two sides and included angle (SAS) Definition: Triangles are congruent if any pair of corresponding sides and their included angles are equal in both triangles. There are five ways to test that two triangles are congruent.