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20-Turquoise
December 1, 2020
Question

Inscribed circle and altitude of triangle ?

  • December 1, 2020
  • 2 replies
  • 8159 views

Hello Everyone.
Given :
inscribed circle of triangle ABC touches its 3 sides at A', B', C'. (see Figure)
A'A'' is a altitude of triangle A'B'C'.
Prove :
C'B / C'A'' = B'C / B'A'' ( blue / green = red / pink )
I.PNG

 Thanks in advance for your time and help.
Regards.
Loi.

2 replies

ttokoro
21-Topaz I
21-Topaz I
December 10, 2020

image.pngimage.pngimage.png

t.t.
25-Diamond I
December 10, 2020

@ttokoro wrote:

Not equal.


No, you are wrong! The two ratios ARE equal. For the example posted approx. 2.24224.

Check your calculations or your interpretation of the position of A". Guess you misinterpreted the latter. A'A'' is perpendicular to B'C' ! The coordinates are approx. A'' (3.92964 / 2.26219).

ttokoro
21-Topaz I
21-Topaz I
December 10, 2020

Thanks. 

image.png

t.t.
21-Topaz II
December 16, 2020

Hi,

the following video is my almost perfect animation about the triangle....:

where: C'B=C1B, C'A''=C1A2, B'C=B1C and B'A''=B1A2

triangolo.jpg