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Old December 3rd, 2008, 08:29 PM
s3a s3a is offline
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Default Circle Question

I don't know what to do on this question and would appreciate detailed help.
Thanks in advance!
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Old December 3rd, 2008, 10:00 PM
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Quote:
Originally Posted by s3a View Post
I don't know what to do on this question and would appreciate detailed help.
Thanks in advance!
triangles ADB and BDC are similar.

so,

\frac{AD}{BD}=\frac{DB}{DC}

\frac{AD}{12}=\frac{12}{5}

AD=\frac{144}{5}=28.8\;\;cm

AC=AD+DC=28.8+5=33.8 \;\;cm

ED = AC-(14+5)=33.8-19=14.8\;\;cm

EC=AC-AE=33.8=14=19.8\;\;cm

In triangle EBD,

EB^2=BD^2+ED^2

EB=\sqrt{(12)^2+(14.8)^2}

EB = 19.05 cm

NOW,

FE \times EB=AE \times EC

FE \times 19.05=14 \times 19.8

FE = 14.6 cm

got it ???
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Old December 4th, 2008, 01:44 PM
s3a s3a is offline
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Thank you very much! I copied and analyzed your work for my assignment but even though the assignment is over with, I'd just like to ask one little question if you can still answer:

How do you prove that triangles ADB and BDC are similar?
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