Question

How do you find the exact value of the third side given `triangle PQR`, `p=126, q=214, mangleR=42`?

Answer 1

`r~=146,95`

Explanation:

You would apply the cosine theorem:

`r=sqrt(p^2+q^2-2pqcos hatR)`

`=sqrt(126^2+214^2-2*126*214*cos42°)~=146,95`