Geometry....

Prakash Panneer · 2006-10-07 01:08:59

A right triangle has legs of length 6 and 8 inches. CD bisects the right angle . Find the lengths of AD and DB.

Last edited by Prakash Panneer (2006-10-07 01:09:47)

John E. Franklin · 2006-10-07 03:16:09

Even though 5 and 5 seem like the right answers, they are not because
the hypotenuse is not perpendicular to the CD-bisector.
However, 10 = AD + DB.
I would use trig and a calculator, Prak.
arctan(6/8) and arctan(8/6), which add to 90 degrees.
two 45 degree angles.
Good luck.

Prakash Panneer · 2006-10-07 03:30:12

Hi Franklin,

Can you give me the detailed answer?

Please...

John E. Franklin · 2006-10-07 03:57:13

I'll work on it...
You have all the angles of a triangle and know one of the sides and need a formula to get the other sides.
I'll google this and get back to you...

John E. Franklin · 2006-10-07 04:20:54

My possible answer: 4 2/7 and 5 5/7

Prakash Panneer · 2006-10-07 04:53:06

Hi,

How did you get this?

Please give me the steps....

John E. Franklin · 2006-10-07 04:55:22

Learn about "law of sines" on internet.
Then the 3 sides of a triangle are just proportional to the sine of the opposite angles
across on the other side of the triangle.

http://img507.imageshack.us/img507/9343/prak4wy0.png

Image is a little poor sorry.

John E. Franklin · 2006-10-07 05:24:26

An interesting thing I just noticed after all that, was an
easier way to do it!!!!
4:3 ratio boosted from 7 to 10 is 40/7:30/7.
Pretty neat!!!!!!!!!!!!!!!!!!!!!!!!!!!

Math Is Fun Forum

#1 2006-10-07 01:08:59

Geometry....

#2 2006-10-07 03:16:09

Re: Geometry....

#3 2006-10-07 03:30:12

Re: Geometry....

#4 2006-10-07 03:57:13

Re: Geometry....

#5 2006-10-07 04:20:54

Re: Geometry....

#6 2006-10-07 04:53:06

Re: Geometry....

#7 2006-10-07 04:55:22

Re: Geometry....

#8 2006-10-07 05:24:26

Re: Geometry....

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