M is the midpoint of side cd of a parallelogram ABCD a line through C parallel to M A intercept ab at P and a produced at our if a is equal to 3.5 CM then the length of DR is
Answers
Answer:
AP∥CR
CP=PD
Since, △APD∼△RCD(AAA)
⇒
DR
DA
=
DC
DP
(CPCT)
⇒
DR
DA
=
2
1
(AsPisthemidpointofCD)
⇒2DA=DR
⇒2DA=DA+AR
⇒DA=AR
Hence Proved DA=AR
Again as, ∠APD=∠QCD&∠BQC=∠APD(AP∥QC),
⇒∠APD=∠QCD=∠BQC
&
∠RDC=∠CBQ(Oppositeof∠is∥gm)
&
∠BCQ=∠CRD(Propertiesof∥gm)
⇒△BQC∼△DCR(AAA)
Now,
As,
⇒△APD≅△CBQ
PD=BQ
or
2
CD
=BQ(AsPisthemidpointofCD)
or
2
AB
=BQ(In∥gmAB=CD)
⇒ Q is the mid-point of AB
Again,
as,
△BQC∼△DCR
CQ
BQ
=
CR
CD
⇒2CQ=CR(AsCD=2BQ)
⇒2CQ=CQ+QR
⇒CQ=QR
Hence Proved CQ=QR
Question:
P is mid point of the side CD of a parallelogram ABCD. A line through C parallel to PA intersect AB at Q and DA produced at R. Prove that DA=AR and CQ=QR
Answer:
Refer attached image, given ABCD is a parallelogram
AP∥CR
CP=PD
Since, △APD∼△RCD(AAA)
⇒
DR
DA
=
DC
DP
(CPCT)
⇒
DR
DA
=
2
1
(AsPisthemidpointofCD)
⇒2DA=DR
⇒2DA=DA+AR
⇒DA=AR
Hence Proved DA=AR
Again as, ∠APD=∠QCD&∠BQC=∠APD(AP∥QC),
⇒∠APD=∠QCD=∠BQC
&
∠RDC=∠CBQ(Oppositeof∠is∥gm)
&
∠BCQ=∠CRD(Propertiesof∥gm)
⇒△BQC∼△DCR(AAA)
Now,
As,
⇒△APD≅△CBQ
PD=BQ
or
2
CD
=BQ(AsPisthemidpointofCD)
or
2
AB
=BQ(In∥gmAB=CD)
⇒ Q is the mid-point of AB
Again,
as,
△BQC∼△DCR
CQ
BQ
=
CR
CD
⇒2CQ=CR(AsCD=2BQ)
⇒2CQ=CQ+QR
⇒CQ=QR