 Hello and welcome to the session. In this session we will describe for a given figure the rotation and reflection that carry it on to itself with the help of reflection symmetry and rotation symmetry. First of all let us discuss line of reflection. Now consider this figure showing the reflection. Now you can see that A dash, B dash, C dash is the reflected image of the triangle. A, B, C and here line of reflection is K. Now you must note that line of reflection always bisects all its perpendicular to the line segment joining the points with their corresponding images. Line bearing P in H, B and in H, B dash perpendicular to the line of reflection K. This line segment B, B dash is also bisected by the line K that is where A, B is equal to A, B dash. This means the range of line segment B, B dash lies on the line of reflection to see that corresponding sides that is a triangle ABC and triangle A dash, B dash, C dash are equal thus the two figures are congruent for means transferring to triangle A dash, B dash, C dash. T that is reflection, length point, distance and collinearity are preserved. Now let us discuss lines of symmetry exactly. Now here, if we fold this figure vertically, the triangle gets divided into two equal halves. The fold is the line of reflection called line of symmetry through this substance. One is the reflected image of the other. Now here you can see when triangle did vertically when we obtain the triangle ABC is thus line of symmetry is the line which carries a triangle or we can say a given figure can do itself. And line of symmetry acts as a mirror across the picture and there can be none, one, two or more than two lines of symmetry. Now let us find lines of symmetry of a square which reflect the square and do itself. Now there are four lines of symmetry of a square because four lines divide the figure into two congruent figures, the horizontal and vertical fold give two congruent rectangles lines of symmetry because rotational symmetry this figure if we rotate this figure by 90 degrees in clockwise direction we will get the same figure the image and the pre-image are indistinguishable it means this figure looks same after a certain amount of rotation and this is called rotational symmetry. Now a figure has rotational symmetry if a rotation of 180 degrees or less clockwise about its center produces an image that fits exactly on the original figure. Thus what we have a rotational symmetry if the figure is its own image under a rotation and the center of rotation is a fixed point. Now from a figure we can find the order of rotation of symmetry it means how many times we can rotate a figure so that it has a rotational symmetry and we can also find the angle of rotation this pentagon now here you can see it has five vertices in rotational symmetry and here we have following rotations first figure the vertex one is a target the figure by a particular angle the position of vertex one and all vertices change but the figure remains same and there is no difference in the pre-image the image in five ways thus angle of rotation is equal to 360 degrees upon order of rotation which is equal to 360 degrees upon order of rotation which is five and this is equal to 72 degrees so here the first figure is rotated at an angle of 72 degrees and we are getting this second figure then the second figure is rotated at an angle of 70 degrees the third figure and so on. Thus rotational symmetry carries the figure onto itself so in this session we have learnt line of reflection symmetry and rotational symmetry and this completes our session hope you all have enjoyed this session.