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=== Prerequisites/Instructions, prior preparations, if any ===
 
=== Prerequisites/Instructions, prior preparations, if any ===
Knowledge about altitude, congruent triangles, parallelogram and its area.
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Knowledge about altitude, trapezium, congruent triangles, parallelogram and its area.
    
=== Materials/ Resources needed ===
 
=== Materials/ Resources needed ===
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# Draw AB  ∥  FC  and  AB is the base.  
 
# Draw AB  ∥  FC  and  AB is the base.  
 
# Draw Parallelograms ABCD  and  ABEF are on the same base AB and between same parallels AB and FC.
 
# Draw Parallelograms ABCD  and  ABEF are on the same base AB and between same parallels AB and FC.
 
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#Identifying plane figures on the same base and between the same parallels
Δ BCE ≅ Δ ADF (By SAS Congruence Criterion)
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#Identify Congruent triangles i.e. Δ BCE ≅ Δ ADF and find the area of triangles
 
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#Find the area of Trapezium ABED by using finding an area tool
ar (BCE) = ar (ADF) =  =
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#What can you say about their areas?
 
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#Proving that parallelograms on the same base and between the same parallels have equal area by using following calculations
( Areas of Congruent figures are equal )
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OBSERVATION / RESULT / OUTCOME :
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Area of the parallelogram ABCD
 
Area of the parallelogram ABCD
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= Area of the Trapezium  ABED  +  Area of the Triangle BCE
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= Area of the Trapezium  ABED  +  Area of the Triangle BCE  
 
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ar (ABCD) = ar (BCE)  +  ar (ABED)
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<nowiki>=            +          =</nowiki>
      
Area of the parallelogram ABEF
 
Area of the parallelogram ABEF
    
= Area of the Trapezium ABED  +  Area of the Triangle ADF
 
= Area of the Trapezium ABED  +  Area of the Triangle ADF
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ar (ABEF)  =  ar (ABED) + ar (ADF)
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<nowiki>=              +        =</nowiki>
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Hence the theorem is verified.
      
=== Evaluation at the end of the activity ===
 
=== Evaluation at the end of the activity ===
# What is the relation between the area of a triangle and area of a parallelogram, if they lie on the same base and between the same parallel lines?
   
# If one rectangle and one parallelogram lying on the same base and between the same parallel lines then what will be area of the rectangle ?
 
# If one rectangle and one parallelogram lying on the same base and between the same parallel lines then what will be area of the rectangle ?
# In a parallelogram ABCD, AB = 7.2 cm and altitudes corresponding to sides AB and AD are respectively 10cm and 8cm. Find AD.
   
Go back to the page - [[KVS Quadrilaterals|click here]]
 
Go back to the page - [[KVS Quadrilaterals|click here]]
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[[Category:Quadrilaterals]]

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