Dhaka regional 2015 secondary/4

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Ragib Farhat Hasan
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Joined:Sun Mar 30, 2014 10:40 pm
Dhaka regional 2015 secondary/4

Unread post by Ragib Farhat Hasan » Mon Jan 18, 2016 7:12 pm

ABCD is a parallelogram and it’s diagonals meet at point O. P and Q are the
midpoints of AO and BC consecutively. ∠A = ∠DPQ and ∠DBA = ∠DQP. If AB=2 unit, then find out the area of ABCD.

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asif e elahi
Posts:185
Joined:Mon Aug 05, 2013 12:36 pm
Location:Sylhet,Bangladesh

Re: Dhaka regional 2015 secondary/4

Unread post by asif e elahi » Mon Jan 25, 2016 9:04 pm

Prove $ABCD$ is a square using spiral similarity.

Absur Khan Siam
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Joined:Tue Dec 08, 2015 4:25 pm
Location:Bashaboo , Dhaka

Re: Dhaka regional 2015 secondary/4

Unread post by Absur Khan Siam » Sun Dec 25, 2016 8:51 am

Can anyone tell me a resource for understanding spiral similarity well?
"(To Ptolemy I) There is no 'royal road' to geometry." - Euclid

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