Introduction to history
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Concept Map
Additional Resources
OER
- Web resources:
- Books and journals
- Textbooks
- NCERT Textbooks – Class 11
- Syllabus documents
Non-OER
- Web resources:
- Historical Thinking : This websites helps in understanding why we should study history and the challenges faced by students and teachers.
- World History : This video series taught by John Green using animations
- Books and journals
- Textbooks
- Syllabus documents (CBSE, ICSE, IGCSE etc)
Learning Objectives
- Identify a triangle
- Recognize interior and exterior angles
- Classifying types of triangles
- Recognize the angle sum property
- Establish relation between interior and exterior angles
Teaching Outlines
Concept 1: Formation of a triangle, elements of a triangle and its measures
- A triangle is a three sided closed figure.
- It is one of the basic shapes in geometry.
- It triangle is a polygon with three edges and three vertices.
- There are three angles in a triangle formed at the three vertices of the triangle.
- Interior and exterior angles in a triangle at a vertex, together form a linear pair.
Activities
- Formation of a triangle: A plane figure formed by three intersecting lines.
- Elements of a triangle: Terms that are associated with triangle.
- Measures in triangle: Parameters that are measured in a triangle.
- Interior and exterior angles in triangle: Angles formed when a triangle is formed.
Concept 2: Types of triangles based on sides and angles
Types of triangles based on angles in the triangle
- Acute triangles are triangles in which the measures of all three angles are less than 90o.
- Obtuse triangles are triangles in which the measure of one angle is greater than 90o.
- Right triangles are triangles in which the measure of one angle equals 90 degrees.
Types of triangles based on sides in the triangle
- Equilateral triangles are triangles in which all three sides are the same length.
- Isosceles triangles are triangles in which two of the sides are the same length.
- Scalene triangles are triangles in which none of the sides are the same length.
Activities
- Types of triangles based on sides: Triangles formed are dependent on measures of sides.
- Types of triangles based on angles: Triangles formed are dependent on measures of angles.