ABCD IS A PARALLELOGRAM, G IS THE POINT ON AB SUCH THAT AG = 2GB, E IS A POINT OF CD SUCH THAT CE = 2DE AND AND F IS A POINT OF BC SUCH THAT BF = 2FC. PROVE THAT

1) ar(ADEG) = ar(GBCE), 2) ar(EGB) = 1/6 ar(ABCD) , 3) ar(EFC) = 1/2 ar(EBF) , 4) ar(EBG) = ar(EFC) , 5) FIND WHAT PORTION OF THE ARE OF PARALLELOGRAM IS THE AREA OF EFG.

1) Given: ABCD is a parallelogram in which AG=2GB,CE=2DE and BF=2FC.

To prove: ar(gmADEG) = ar(gmGBCE)

Proof: Since ABCD is a parallelogram, we have AB CD and AB =CD.

∴ BG=AB 

and DE= CD=AB 

∴   BG = DE 

∴ ADEH is a gm    [since AH is parallel to DE and AD is parallel to HE]

ar(gmADEH )=ar(gmBCIG )...........(i) 

[since DE=BG and AD=BC parallelogram with corresponding sides equal]

area ( ΔHEG)=area( ΔEGI).............(ii)

[diagonals of a parallelogram divide it into two equal areas]

From (i) and (ii), we get,

ar(gmADEH )+area ( ΔHEG)=ar(gmBCIG )+area( ΔEGI)

ar(gmADEG) = ar(gmGBCE)

2)

Height,  h of gm ABCD and ΔEGB is the same.


Base of ΔEGB =  
area(ABCD) = hAB 
area(EGB) =  


area(EGB) =

 

3)  Let the distance between EH and CB = x


⇒ Area(EFC) =    Area(EBF)

 

4) If g = altitude from AD to BC 
area(EFC) =
⇒ area(EFC) = area(EBG) 
 

5) area(EFG) = area(EGB)+area(EBF)+area(EFC) 


 

 

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AB=DC , AG=EC , GE(COMMON) , BC=AD IF ALL THE SIDES OF BOTH THE QUADRILATERAL ARE EQUAL TO EACH OTHER SO THE AREA OF BOTH QUADRILATERAL ARE EQUAL

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