Trigonometry – Law of Cosines
Cue presidential music: "Hello, my fellow YayMathers. It is indeed my great and honored pleasure, to teach you how to solve triangles using the Law of Cosines, from right within the Oval Office. It's a great follow up from our epic lesson on the Law of Sines. These topics are not only useful within Trigonometry, but also for Algebra 2, Pre calculus, and Calculus. I'm grateful to use this platform in this way, to advance the Yay Math mission. And so I'll say once again, YAY MATH!"