6th Class Mathematics Symmetry

 Symmetry

• A figure has a line symmetry if a line can be drawn dividing the figure into two identical parts. The line is called a line of symmetry.

• A line segment is symmetrical at its perpendicular bisector.

• A figure may have no line of symmetry, only one line of symmetry, two lines of symmetry or multiple lines of symmetry.

• A line symmetry is closely related to mirror reflection. When dealing with mirror reflection, we have to take into account the left right changes in orientation.

• A figure may have a vertical or a horizontal line of symmetry.

• Of the digits 0 to 9, only 1, 3 and 8 have a horizontal line of symmetry, 8 has vertical line of symmetry also.

• Alphabets of English, A to...... Z have different lines of symmetry.

(i) The letter of the English alphabet with no line symmetry are F, G, J, L, N, P, Q, R, S and Z.

(ii) The letters A, M, T, U, V, W and Y have only vertical line of symmetry.

(iii) The letters B, C, D, E, and K have only horizontal line of symmetry.

(iv) The letters H, I and X have both vertical and horizontal lines of symmetry.