V'ver leans over and points to triangles LKA and DVA. "You see how they share a common angle with A? They're mirror images. Side K is congruent to side V." He lightly outlines the sides with his pencil to make his point a little clearer. "You see? Any time two angles on two different triangles like that have the same name, they'll always be equal. You're looking at it like they're two completely different things, but they're really two halves of the same whole."