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solve 4 , 5 and 6
Answers
4)
ABCD is ∥gm
AB∥CD
AE∥FC
⇒AB=CD
AB= 1/2
CD
AE=EC
AECF is ∥gm
In △DQC
F is mid point of DC
FP∥CQ
By converse of mid point theorem P is mid point of DQ
⇒DP=PQ (1)
∴AF and EC bisect BD
In △APB
E is mid point of AB
EQ∥AP
By converse of MPT ( mid point theorem )
Q is mid point of PB
⇒PQ=QB (2)
By (1) and (2)
⇒PQ=QB=DP
AF and EC bisect BD..
5)
In △ADC,S is the mid-point of AD and R is the mid-point of CD
In △ABC,P is the mid-point of AB and Q is the mid-point of BC
Line segments joining the mid-points of two sides of a triangle is parallel to the third side and is half of of it.
∴SR∥AC and SR= 1/2
AC ....(1)
∴PQ∥AC and PQ= 1/2
AC ....(2)
From (1) and (2)
⇒PQ=SR and PQ∥SR
So,In PQRS,
one pair of opposite sides is parallel and equal.
Hence, PQRS is a parallelogram.
PR and SQ are diagonals of parallelogram PQRS
So,OP=OR and OQ=OS since diagonals of a parallelogram bisect each other.
Hence proved.
Answer:
(4)
ABCDllgm
ABllCD
AEllFC
→AB=CD
CD
AE=EC
AECF is llgm
in∆DQC
F is midpoint of DC
FPllCQ
By Converse of mid point theorem
p is the mid point of DQ
DP=PQ. (1)
AF and EC bisect BD