Kay wants to know the length of large pond on property. One stake is at 50m with an angle of 21 degrees. The 65m from the other end of the lake and the angle is 26 degrees. How long is pond?

Not quite sure what the "at 50m" means.

Also, knowing the other stake is 65m from the end of the pond does no good.

Now, if the two stakes are at the ends of the pond, and the given distances are as measured from the observation point, then the distance between the stakes can be calculated using the law of cosines, since you have two sides and the included angle.

If not, then you had better describe the situation more clearly.