`=5, b=4andtanc/2=sqrt(7/9)` then side 'c'|In a AABC, a = 5, b = 4 and tanis equal to

Options

A. 6
B. 3
C. 2
D. None of these

Answer

A

Explanation

`"tan"^(2)(C)/(2)=((s-a)(s-b))/(s(s-c))`
`=((9+c-10)(9+c-8))/((9+c)(9-c))=(c^(2)-1)/(81-c^(2))`
`therefore(7)/(9)=(c^(2)-1)/(81-c^(2))rArrc=6`