the line joining midpoint of the two sides of a triangle is parallel to the third side and is of it is
Answers
Answer:
]|I{•------» Hҽყ «------•}I|[
Step-by-step explanation:
Given: ABCD is a Triangle where E & F are Mid points of AB & AC respectively
To Prove: EF║BC
Construction: Through C draw a Line Segment Parallel to AB & Extend EF To meet This Line at D
Proof: Since AB║CD ( By Construction )
With Transversal AD
∠AEF = ∠CDF (Alternate Angles)......( 1 )
In Δ AEF & ΔCDF
In ∠ AEF & ∠CDF .....From ( 1 )
∠ AFE & ∠CFD ...... ( Vertically opposite Angle )
AF = CF ( As F is mid point of AC )
Δ AFE ≅ ΔCFD ( AAS Rule )
So, EA = DC (CPCT)
But, EA = EB ( E is the mid point of AB )
Hence, EB = DC
Now,
In EBCD,
EB ║DC & EB = DC
Thus, One pair of opposite Sides is Equal and Parallel.
Hence, EBCD is a Parallelogram
Since, opposite sides of parallelogram are parallel
So, ED║BC
i,e EF║BC
Hence, Proved
Given: ABCD is a Triangle where E & F are Mid points of AB & AC respectively
To Prove: EF║BC
Construction: Through C draw a Line Segment Parallel to AB & Extend EF To meet This Line at D
Proof: Since AB║CD ( By Construction )
With Transversal AD
∠AEF = ∠CDF (Alternate Angles)......( 1 )
In Δ AEF & ΔCDF
In ∠ AEF & ∠CDF .....From ( 1 )
∠ AFE & ∠CFD ...... ( Vertically opposite Angle )
AF = CF ( As F is mid point of AC )
Δ AFE ≅ ΔCFD ( AAS Rule )
So, EA = DC (CPCT)
But, EA = EB ( E is the mid point of AB )
Hence, EB = DC
Now,
In EBCD,
EB ║DC & EB = DC
Thus, One pair of opposite Sides is Equal and Parallel.
Hence, EBCD is a Parallelogram
Since, opposite sides of parallelogram are parallel
So, ED║BC
i,e EF║BC
Hence, Proved
HOPE you understand ❤️❤️❤️