Symmetry is an essential concept in mathematics. It deals with the graphs of mathematical equations and the position of their points in correlation to a set of perpendicular axes. Circles are perfect objects in mathematics because they possess all three possible types of symmetry. The three types of symmetry include symmetry to the origin, symmetry to the xaxis and symmetry to the yaxis.
The Coordinate Axes

In mathematics, the notion of symmetry stems from the "x" and "y" coordinate axes. The coordinate axes are an arrangement of two lines that make a right angle with one another  one vertical, the yaxis, and one horizontal, the xaxis. The origin is the point at which both lines crisscross. Each line contains equally spaced partitions or units that the mathematician uses to determine the values and measurements of graphs of functions.
Origin Symmetry

Mathematicians typically situate the axis to a circle by superimposing the origin of the axes on top of the center of the circle. This method of placement makes the equations of a circle much easier to manipulate because every point on the circle's edge is an identical distance from the origin. In this case, the circle possesses symmetry to the origin  the circle's mirror image appears above and below the xaxis as well as to the left and right of the yaxis.
Xaxis Symmetry

Some graphs contain a special property that makes them perfectly symmetric with the xaxis. The xaxis is horizontal on the coordinate axes and contains the unknowns or input values of a function. A graph is symmetric about the xaxis if its mirror image appears both above and below the xaxis. In mathematical terms, the function will produce identical "x" values on either side of the xaxis.
Yaxis Symmetry

The yaxis is the vertical coordinate axis and contains the output values of a mathematical equation for all inputted yvalues. Symmetry about the yaxis abides by the same principles as symmetry about the origin and symmetry about the xaxis. The only difference is that the graph's mirror image shows up on either side of the yaxis. Mathematically, it is the opposite of symmetry about the xaxis  the function will produce identical "y" values on either side of the yaxis.
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