Isn't this cosine law because he has all 3 angles.

See, 90+64-180= 26

So thats the other side.

And with 3 angles you do cosine, or sine law. I forgot which one.

Doesn't matter.. it's easy from there.

If you STILL can't figure it out from there that's sad, and I guess I'll just answer it for you...

Actually I drew it, and it looks like you can do simple sohcahtoa....