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In the given figure: AB//FD, AC//GE and BD = CE; prove that: i. BG = DF ii. CF = EG - Mathematics

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प्रश्न

In the given figure: AB//FD, AC//GE and BD = CE;

prove that: 

  1. BG = DF     
  2. CF = EG   

 

योग
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उत्तर

In the given figure AB || FD,

⇒ ∠ABC =∠FDC

Also AC || GE,

⇒ ∠ACB = ∠GEB

Consider the two triangles ΔGBE and ΔFDC

∠B = ∠D             ...(Corresponding angle)

∠C = ∠E             ...(Corresponding angle)

Also given that

BD = CE

⇒ BD + DE = CE + DE

⇒ BE = DC

∴ By Angle-Side-Side-Angle criterion of congruence

ΔGBE ≅ ΔFDC

∴ `"GB"/"FD" = "BE"/"DC" = "GE"/"FC"`

But BE = DC

⇒ `"BE"/"DC" = "BE"/"BE"` = 1

∴ `"GB"/"FD" = "BE"/"DC"` = 1

⇒ GB = FD

∴ `"GE"/"FC" = "BE"/"DC"` = 1

⇒ GE = FC

shaalaa.com
Criteria for Congruence of Triangles
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 9: Triangles [Congruency in Triangles] - Exercise 9 (A) [पृष्ठ १२२]

APPEARS IN

सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 9 Triangles [Congruency in Triangles]
Exercise 9 (A) | Q 11 | पृष्ठ १२२

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