Difference between revisions of "Elements of a triangle"
Jump to navigation
Jump to search
| Line 33: | Line 33: | ||
|||| | |||| | ||
|- | |- | ||
| − | ||||| | + | |.|||| |
|- | |- | ||
| − | ||||| | + | |. |
| + | |||| | ||
|} | |} | ||
* For each of the triangles observe (inspect visually) which is the longest side and which is the shortest side | * For each of the triangles observe (inspect visually) which is the longest side and which is the shortest side | ||
| Line 45: | Line 46: | ||
!Smallest side | !Smallest side | ||
|- | |- | ||
| − | | | + | |. |
| | | | ||
| | | | ||
| Line 51: | Line 52: | ||
| | | | ||
|- | |- | ||
| − | | | + | |. |
| | | | ||
| | | | ||
| Line 57: | Line 58: | ||
| | | | ||
|- | |- | ||
| − | | | + | |. |
| | | | ||
| | | | ||
| Line 78: | Line 79: | ||
ex-side3,angle3 | ex-side3,angle3 | ||
|- | |- | ||
| − | ||||||||||||||| | + | |. |
| + | |||||||||||||| | ||
|- | |- | ||
| − | ||||||||||||||| | + | |. |
| + | |||||||||||||| | ||
|- | |- | ||
| − | ||||||||||||||| | + | |. |
| + | |||||||||||||| | ||
|} | |} | ||
| − | + | '''Evaluation at the end of the activity''' | |
| − | + | *Have the students been able to identify the elements in a triangle? | |
| − | + | *Have they been able to extrapolate any connection between the angle and side in a triangle? | |
Revision as of 10:21, 12 April 2019
Elements of a triangle are the angles that are formed when three lines intersect and the segments that mark the triangle are sides.
Objectives
- To understand the elements of a triangle
Estimated Time
Prerequisites/ Instructions, prior preparations, if any
Prior knowledge of point, lines, angles, parallel lines
Materials/ Resources needed
- Digital : Computer, Geogebra application, projector.
- Non digital : Worksheet and pencil,6-8 strings (preferably in different colours)
- Geogebra files : “Elements of a triangle.ggb”
Process (How to do the activity)
- -----Students work individually but in their groups.
- Take the strings and place them in such a way as to make a closed figure.
- What is the smallest number of strings with which you can form a closed figure?
- What is this figure called?
- Can you just draw the lines along the strings and see what you get?
- When you drew, what did you draw? (Was it a line or was it an angle or was it a line segment?). It is a lime segment – how many line segments are there?
- When two line segments joined, what is it called? (A vertex). How many vertices are there?
- Is there any angle formed when you made this figure? How many angles were formed? How many angles lie within the closed figure?
- Show a simple Geogebra file with triangles – Use this file to demonstrate that every triangle has the elements - vertices, sides and angles
- How many triangles were formed? Were there any strings left over?
- For each of the triangles trace the shape on the book and write down the elements of the triangle in the following format
| Vertices | Sides | Angles |
|---|---|---|
| . | ||
| . | ||
| . |
- For each of the triangles observe (inspect visually) which is the longest side and which is the shortest side
| Triangle name | Largest angle | Largest side | Smallest angle | Smallest side |
|---|---|---|---|---|
| . | ||||
| . | ||||
| . |
- Allow the students to explore if there is any connection between the two?
- After the students see the Geogebra file, they can attempt an alternative worksheet like below
| Side 1 | Angle 1
(opposite angle) |
! Side 2 | Angle 2
(opposite angle) |
! Side 3 | Angle 3
(opposite angle) |
! Largest side and angle
ex-side1,angle1 |
! Smallest side and angle
ex-side3,angle3 |
|---|---|---|---|---|---|---|---|
| . | |||||||
| . | |||||||
| . |
Evaluation at the end of the activity
- Have the students been able to identify the elements in a triangle?
- Have they been able to extrapolate any connection between the angle and side in a triangle?