Let's consider a code example showing what would be allowed (or not) using different levels of inheritance: 1  class BaseClass {}; void freeStandingFunction(BaseClass* b); class DerivedProtected : protected BaseClass { DerivedProtected() { freeStandingFunction(this); // Allowed } };
Definition of Horizontal Axis. Horizontal means flat or level. Horizontal axis is the x-axis on a graph. The blue number line in the figure below is the x-axis, the horizontal axis.
1 Step 1: The coordinate plane is formed by the intersection of two number lines, a horizontal number line and a vertical number line. The horizontal number line is called the x-axis.  Step 2: Graph 2 has the point P on the horizontal line i.e., on the x-axis.