
Triangle's side
Hey!
I have this problem: In triangle $\displaystyle ABC$, $\displaystyle AC$ is $\displaystyle 9$, $\displaystyle BC$ is $\displaystyle 7$. Point $\displaystyle M$ is the midpoint of $\displaystyle AB$, and $\displaystyle CM$ is also $\displaystyle 7$. What is the length of $\displaystyle AB$
The only way to solve the problem, that I can think of is using the cosine rule, but it is said that the problem could be solved without using trigonometry. Can anyone give me an idea how?

Re: Triangle's side
There's an easy solution using Stewart's theorem, but that's about all I see.

Re: Triangle's side