Determiner-r-et-R-voir-figure-Sachant-aue-C-120-AB-12-

Question Number 200761 by a.lgnaoui last updated on 23/Nov/23

Determiner r et R (v o i r f i g u r e)

Sachant aue : ∡ C = 120 : A B = 12

Commented by a.lgnaoui last updated on 23/Nov/23

Commented by mr W last updated on 23/Nov/23

d o y o u m e a n “ r = ? a n d R = ?^{″} o r

“ r + R = ?^{″} ?

Commented by a.lgnaoui last updated on 23/Nov/23

find r and R

Commented by a.lgnaoui last updated on 23/Nov/23

(A and B are the centre of circle : radius r)

Commented by mr W last updated on 23/Nov/23

i t h i n k y o u c a n n o t d e t e r m i n e r a n d

R . y o u c a n o n l y d e t e r m i n e t h e s u m

o f r a n d R, i . e . r + R .

Answered by mr W last updated on 23/Nov/23

A C = r + R - 5

B C = r + R - 3

s a y s = r + R

{(s - 5)}^{2} + {(s - 3)}^{2} + (s - 5) (s - 3) = 12^{2}

3 s^{2} - 24 s - 95 = 0

s = \frac{12 + \sqrt{429}}{3} \approx 10.9

Commented by a.lgnaoui last updated on 26/Nov/23

thanks