Symmetry of geometric figures

Hello kids, Previously we have discussed about analytical geometry problems and now we will discuss Symmetry of geometric figures, congruence of geometric figures for grade IV students of Maharashtra Board Syllabus.

Symmetry of geometric figures .

Mirror symmetry: A geometric figure represents the mirror symmetry when each point let B in the plane there found a point B', so that the segment BB'is perpendicular to the plane “P” and is divided by this plane into two BA = AB'. Then this palne is called symmetry plane. The best example of mirror symmetry is our hand, they fit on to one another completly. (for more reading click on geometry help).

Central Symmetry: A geometric figure is said to be central symmetric, if for center C each point say A there exists a point E on the figure, and segment AE goes through the center C divided in two parts Ac = AE, then this point is called a symmetric center.

Rotation Symmetric: A geometric figure said to has rotation symmetry if we turn the figure by 360degree / n, where “n” is any integer, a straight line say AB, this line is called symmetry axis, coincides completely with its initial point.

Example : At n = 2, we have axial symmetry.(Know more about geometry in broad manner here,)

Now we will discuss the congruence of geometric figures. When we talk about congruence the first question arises in our mind is:

What is congruence ? The answer is, the term congruence defines the fact that when one object completely coincides with other. That is they are the mirror image of one another. When we put one object on to the other one it completely hides the other one. For example gloves of our hand. Glove of right hand can't be worn on left and vice versa. They are called the mirror images.

In other word we can say,

Two figures are called congurent if one shape can become other using turns, flips, sides..

Rotation: Rotation means turning around a center, in this process teh center at any point on the figure remains the same. Rotation is called the turn.

Reflection: Reflection has the same size as the original figure and also every point in the reflection has the same distance from the central line. This central line is also called teh mirror line. Reflection is called flip. Here below is the example of reflection alog x - axis and y – axis.

Along x – axis

Along y – axis

Translation: In terms of geometry translation means moving. By means of moving we means without rotating or resizing and etc. Translation means slide.

To translate any figure every point of teh figure must move:

1. In the same direction

2. same distance.

Translation is done either by x and y axis or by angle and distance.

This is all about the geometric figures and if anyone want to know about Percents problems in mathematics then they can refer to Internet and text books for understanding it more precisely. Read more maths topics of different grades such as Decimals and Place Values in the next session here.