Median, bisector and the height of the triangle презентация

Goals lesson
Education: Introduction of new concepts heights, medians and bisectors of a triangle.
Educational: to educate the ability to listen and hear.
Developing: Develop a stable cognitive interest in the study of geometry

Plan lesson
Greeting (2min)
Organizing time (3min)
To explain the new material (15min)
Work together with the teacher (15min)
Reflection (5min)
Give homework (2min)
Summarizing time (3min)

The properties of the medians of a triangle
1. The median divides the triangle into two triangles of equal area.
2. The medians of a triangle intersect at one point, which divides each of them in the ratio of 2:1, starting from the top. This point is called the center of gravity of the triangle.
3. The whole triangle is divided into six their medians of equal triangles.

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Each triangle can be carried out three bisectors that intersect at a single point,
usually denoted Latin letter I.
The point of intersection of the bisectors of the triangle (I) - Center the in circle.

Properties triangle bisectors
The bisector of angle - a locus of points equidistant from the sides of the angle.
Bisector internal angle of a triangle divides the opposite side into segments proportional adjacent sides: x / y = a / b.
The point of intersection of the bisectors of the triangle is the center of a circle inscribed in the triangle.

The height of the triangle - the perpendicular drawn from the vertex
triangle to the line containing the opposite side.