Concurrent Lines within a Triangle How can you

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Concurrent Lines within a Triangle How can you best describe the different lines within

Concurrent Lines within a Triangle How can you best describe the different lines within a triangle?

Vocabulary Concurrent lines – Three or more lines that intersect at a common point.

Vocabulary Concurrent lines – Three or more lines that intersect at a common point. Point of concurrency – The point where the lines intersect. Equidistant – Equal distance.

Special Lines of a Triangle Angle Bisector Lines A line drawn from the vertex

Special Lines of a Triangle Angle Bisector Lines A line drawn from the vertex of a triangle to the opposite side of a triangle. The angle bisector line bisects the angle from the vertex. There are three angle bisector lines.

Special Lines of a Triangle ¡ ¡ The point of concurrency is called the

Special Lines of a Triangle ¡ ¡ The point of concurrency is called the incenter. The incenter is equidistant to the sides and the line from them to the sides is perpendicular.

Special Lines of a Triangle Perpendicular Bisector Lines A line drawn from the side

Special Lines of a Triangle Perpendicular Bisector Lines A line drawn from the side of one triangle to the opposite side. It bisects the side it’s drawn from and creates a 90 degree angle with that side. There are three perpendicular bisector lines for each triangle.

Special Lines of a Triangle ¡ ¡ ¡ The point of concurrency is called

Special Lines of a Triangle ¡ ¡ ¡ The point of concurrency is called the circumcenter. The circumcenter is equidistant to the vertices of a triangle. It’s possible for the circumcenter to be located on or outside of the triangle.

Special Lines of a Triangle Some perpendicular bisector lines can be drawn from the

Special Lines of a Triangle Some perpendicular bisector lines can be drawn from the vertex of a triangle. Only true with equilateral triangles and isosceles triangles.

Special Lines of a Triangle Altitudes A line drawn from the vertex to the

Special Lines of a Triangle Altitudes A line drawn from the vertex to the opposite side. The altitude creates a right angle with the side. Some altitudes can be drawn outside of a triangle. Only obtuse triangles. There are three altitude lines.

Special Lines of a Triangle ¡ The point of concurrency is called the orthocenter.

Special Lines of a Triangle ¡ The point of concurrency is called the orthocenter.

Special Lines of a Triangle Median A line inside the triangle drawn from the

Special Lines of a Triangle Median A line inside the triangle drawn from the vertex to the opposite side. The median bisects the opposite side. There are three median lines.

Special Lines of a Triangle The point of concurrency is called the centroid. The

Special Lines of a Triangle The point of concurrency is called the centroid. The centroid is located 2/3 of the way from the vertex. The portion of the median from the centroid to the vertex is double the distance of the centroid the opposite side.

Vocabulary ¡ ¡ ¡ Equidistant – Equal distance. Incenter – the point of concurrency

Vocabulary ¡ ¡ ¡ Equidistant – Equal distance. Incenter – the point of concurrency of the angle bisectors lines. Orthocenter – the point of concurrency of the altitudes.

Vocabulary ¡ ¡ Centroid – the point of concurrency of the medians Circumcenter –

Vocabulary ¡ ¡ Centroid – the point of concurrency of the medians Circumcenter – the point of concurrency of the perpendicular bisectors

Special Lines The circumcenter is equidistant from the vertices of a triangle. The circumcenter

Special Lines The circumcenter is equidistant from the vertices of a triangle. The circumcenter will meet on the outside of a triangle in an obtuse triangle. The circumcenter will meet on the triangle in a right triangle.

Special Lines The incenter is equidistant from each side of the triangle. The centroid

Special Lines The incenter is equidistant from each side of the triangle. The centroid is two-thirds the distance from each vertex to the midpoint of the opposite side.