If in a triangle `ABC, (s-a)(s-b)= s(s-c),` then angle `C` is equal to

With usual notation,if in a triangle ABC ,(s-a)/(5)=(s-b)/(6)=(s-c)/(7), then value of cos C is-

In a triangle ABC, (s-a)/11=(s-b)/12=(s-c)/13 , then tan^2 (A//2)=

If in a triangle ABC, (s-a)/11=(s-b)/12=(s-c)/13. Then 429cot^2 ( A/2 ) is equal to

In a triangle ABC, (s-a): (s-b) : (s -c) ::11 : 8: 7 where s is semi perimeter a,b,c are sides find the ratio of a:b:c

In a triangle ABC, if (a-b)/(b-c)= (s-a)/(s-c) , then r_1,r_2,r_3 are in

If in a triangle ABC,(s-a)/(11)=(s-b)/(12)=(s-c)/(13) .and k tan^(2)(A/2)=429, then (sqrt(k))/(11)