The right triangle has one 90 degree angle and two acute (< 90 degree) angles. Since the sum of the angles of a triangle is always 180 degrees... y + z = 90 degrees. The two sides of the triangle that are by the right angle are called the legs... and the side opposite of the right angle is called the hypotenuse.
They were called the Hollywood 10 and accused of being communist. I don't think you would find many people who can name them all.
McCarthy was not the only individual to seek out potential communists. The House Committee on Un-American Activities (HUAC) targeted the Hollywood film industry. Actors, writers, and producers alike were summoned to appear before the committee and provide names of colleagues who may have been members of the Communist Party.