Answer: cos(Q) = 5/13
=========================================================
Work Shown:
The triangles are similar, which means the corresponding angles are congruent. In this case, we can say angle K = angle Q. Note how K and Q are the second letters of JKL and PQR respectively. The order matters.
Because angle K = angle Q, we can use information from triangle JKL to get information about triangle PQR.
We can say the following:
cos(angle) = adjacent/hypotenuse
cos(K) = LK/JK
cos(K) = 5/13
cos(Q) = 5/13 ... plug in K = Q
