Respuesta :

taskmasters
We have the following givens:
a=25 
b=16
c=9
We can make use of the Laws of Cosines in solving the angle A such as:
cos A = (b²+c²-a²)/2bc
cos A =((16)²+9²-(25)²)/1*16*9
A=180°

tan (A/2)=tan(180/2)