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Similar and congruent triangles (view source)
Revision as of 11:06, 2 November 2013
, 11:06, 2 November 2013→Concept #1. What are similar triangles ? Their characteristics.
= Teaching Outlines =
= Teaching Outlines =
==Concept #1. What are similar triangles ? Their characteristics.==
==Concept #1. What are similar triangles ? ==
===Learning objectives===
===Learning objectives===
===Notes for teachers===
===Notes for teachers===
===Activity No # ===
===Activity No # 1 SIMILAR TRIANGLES===
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''[http://www.karnatakaeducation.org.in/?q=node/305 Click to Comment]''</div>
''[http://www.karnatakaeducation.org.in/?q=node/305 Click to Comment]''</div>
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*Estimated Time
*Estimated Time:45 minutes.
*Materials/ Resources needed
*Materials/ Resources needed:
*Prerequisites/Instructions, if any
Laptop, geogebra file, projector and a pointer.
*Multimedia resources
*Prerequisites/Instructions, if any:
# The students should have prior knowledge of triangles , sides , angles , vertices .
# They should know meaning of the terms 'similar' and 'proportionate'.
# They should be able to identify the corresponding sides.
# They should know how to find ratio.
# They should know to find area and perimeter of triangles.
# The students should have clarity between the terms congruent and similar.
*Multimedia resources: Laptop
*Website interactives/ links/ / Geogebra Applets
*Website interactives/ links/ / Geogebra Applets
*Process/ Developmental Questions
*Process:
*Evaluation
# The teacher can bring different sized photographs got from same negative like stamp size, passport size and a post card size . Compare them and say that all photos are look alikes and are proportionate . only the size differs.
*Question Corner
# She can also mention about scale concept in graphical representation.
# Hence similar triangles are the same proportionate triangles but of different sizes.
# Two triangles are similar if they have:
* all their angles equal
* corresponding sides in the same ratio
# In similar triangles, the sides facing the equal angles are always in the same ratio.
# Application of this finds its use in finding the unknown lengths in similar triangles . For this :
Step 1: Find the ratio of corresponding sides in pairs of similar triangles.
Step 2: Use that ratio to find the unknown lengths.
*Developmental Questions:
# Look at the shape of both triangles being formed? (look alikes )
# As I increase /decrease the size of triangles do you see that the measures are changing proportionately ?
# Can any one explain what exactly proportionately means ?
# Can you identify the corresponding sides and angles ?
*Evaluation:
# Name the corresponding sides.
# Compare the perimeters of two similar triangles.
# What are equiangular triangles ?
*Question Corner:
# Compare the ratio of corresponding sides of similar triangles. What do you infer ?
# How can one draw similar triangles if only one triangles sides are given ?
# Discuss the applications of similar triangles in finding unknowns in real life situations.
# Give examples where one uses the concept of similarity.
===Activity No # ===
===Activity No # ===
