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#284 Re: This is Cool » Miscellany » 2019-07-16 14:40:30

ganesh wrote:

This plant is native to Southeast Asia, including Myanmar, India, Indonesia, Sri Lanka, and other neighboring countries, as well as some parts of Australia and Africa.

Yes, this plant is often used for ornaments at city parks in my country (and maybe your country as well, assuming you are from India). It's beautiful and relaxing when you're under it, until one day I looked up to the leaves and noticed a hanging spherical web containing multiple wiggling maggots. It gave me goosebumps and made me immediately left.

#285 Re: This is Cool » Miscellany » 2019-07-12 19:01:50

ganesh wrote:
Monox D. I-Fly wrote:
ganesh wrote:

For many years, scientists classified tigers into nine subspecies: six living subspecies and three extinct ones.

Saber-toothed tiger, Smilodon, and...?

I think they were : The Bali Tiger (Panthera tigris balica), The Caspian Tiger (Panthera tigris virgata), and The Javan Tiger (Panthera tigris sondaica).

I... forgot that "extinct" doesn't always mean "prehistoric". Silly me.

#286 Re: This is Cool » Miscellany » 2019-07-11 15:50:44

ganesh wrote:

For many years, scientists classified tigers into nine subspecies: six living subspecies and three extinct ones.

Saber-toothed tiger, Smilodon, and...?

#288 Re: Help Me ! » [ASK] Question About Circle and Parallelogram » 2019-07-07 20:17:06

Well, anyway, it's solved. Thanks for your help.

#290 Re: Help Me ! » [ASK] Question About Circle and Parallelogram » 2019-07-07 13:12:50

bob bundy wrote:

hi Monox D. I-Fly

Does this look right for the problem?

https://i.imgur.com/ilpQUFj.gif

No, ABCD is named counter clockwise from the bottom left.

#296 Help Me ! » [ASK] Question About Circle and Parallelogram » 2019-07-06 13:21:41

Monox D. I-Fly
Replies: 5

A parallelogram ABCD has angle A = angle C = 45°. Circle K with the center C intercept the parallelogram through B and D.  AD is extended so that it intercepts the circle at E and BE intercepts CD at H. The ratio of the area of triangle BCH and triangle EHD is ....

Here I got that triangle BCH and triangle EHD is similar with angle BCH = angle HDE = 45°, angle CHB = angle DHE = 112.5°, and angle CBH = angle DEH = 22.5°. The area of triangle BCH is ½ × CH × h, where h is the parallelogram's height. The area of triangle EHD is ½ × (r - CH) × r. I stuck at the ratio is (CH × h) : ((r - CH) × r). How do I simplify that? Problem is, I don't know CD's length, so I can't approximate the ratio between CH and DH.

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