CPM Homework Help : CCA2 Problem 4-88

Think about the axis system in the two-dimensional coordinate plane. What is the equation of the $x$ -axis? What is the equation of the $y$ -axis?

Hint:

What are the $y$ -values for all the points on the $x$ -axis?
How would you write an equation to describe that?
Make a list of several points on the $x$ -axis if you need to.

More Help:

Similarly, what are the $x$ -values of all the points on the vertical axis?