The X-axis, which is the horizontal axis, on most Excel charts does not use numeric intervals like the vertical Y-axis does. The X-axis contains either strings of text or a date under each set of data ...

Graphs in Microsoft Excel typically chart time on the horizontal axis. Time is the independent variable in most relationships and dependent variables appear on the vertical axis. Some charts, though, ...

If you understand the definition of a mathematical function, a good way to judge it is that any line drawn parallel to the y-axis intersects with the values in the function’s curve only once. The same ...