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.
Joseph McCarthy then accused several innocent citizens, most notably Owen Lattimore, of being associated with communism. Along the way, he had Louis Budenz, the former editor of The Daily Worker, back his accusations with evidence that was circumstantial at best, for Budenz was only using information he had heard from other people as much as 13 years prior.