How to say 'X' in Spanish: Equis; that's the letter X. You try it.
If you want to say something like 'I need an x-ray', you would say, 'Necesito un rayo-x." Go ahead, try it. If I ask you, "Do you need an x-ray?" "?Necesitas un rayo-x?" you would say, "Si, necesito un rayo-x." Go ahead, try it. ?Necesitas un rayo-x? That's how to say 'X' in Spanish.