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Maths Problem

PostPosted: Tue Jun 17, 2008 2:35 pm
by siddhartha_dutta
how to solve this: http://techrecipe.blogspot.com/2008/06/test.html

Here DL&BM are angle bisectors
and we have to prove that <BMC+<ALD= 1/2 (<ADC+<ABC>)

Re: Maths Problem

PostPosted: Sun Aug 31, 2008 7:57 pm
by shubham
some easy ways to solve problems :lol:

Re: Maths Problem

PostPosted: Fri May 15, 2009 8:49 am
by pspoornima
Hello Siddharth,

Please find the answer for your question.

In Parallelogram ABCD,

AB II DC
AL II MC (Extensions of AB and DC Rescpectively)

Ang ABM = Ang BMC (Alternate Angles) (1)
Ang ALD= Ang LDC ( Alternate Angles) (2)


Ang ABM = 1/2 Ang ABC ( Given BM is angle bisector of ang ABC)
Ang LDC = 1/2 Ang ADC ( Given DL is angle bisector of ang ADC)

Ang ABM+LDC = 1/2(Ang ABC+Ang ADC) (3)

But Ang ABM = Ang BMC & Ang LDC =ALD ( from 1 & 2)

Therefore
Ang BMC+ Ang ALD= 1/2(Ang ABC+ Ang ADC) ( from 1, 2 & 3)

Thanks & Regards,
Poornima.