# How do you know which variable is the "x" and the "y"?

Take for example the equation $\text{y = x"^2}$. The values that you input for x will determine the values of y. So x is the independent variable and y is the dependent variable.
The same would be true if the equation was $\text{b = a"^2}$. The a would be the x-variable (independent variable), and b would be the y-variable, (dependent variable).