In this function, y is the dependent variable and x is the independent variable. Variable used in an experiment or modelling can be divided into three types:  dependent variable ,  independent variable , or other.
About 70% of men have an eye dominance that matches their handedness. BUT, 30% do not. Most right handers have a dominant right eye and the bulk of southpaws a dominant left. These are the people who are well advised to shoot both eyes open (assuming that they are shooting from their strong shoulder).
This is a condition called pseudostrabismus or false strabismus. The appearance of crossed eyes may be due to extra skin that covers the inner corner of the eyes or a wide bridge of the nose. Usually, the appearance of crossed eyes will go away as the baby's face begins to grow.