Let me Explain the meaning of term of term reflection symmetry i.e If an image is reflected across a line of symmetry , axis either through X or Y,the two halves of same image are identical or symmetrical or look alike.For example Human body has a line of symmetry, the alphabets A, X, U,E has 1, 2, 1,1 line of symmetry.In polygons Isosceles triangle,equilateral triangle has 1 and 3 lines of symmetry.
So , Reflectional symmetry is the quality a design has if it maintains <u>Symmetry i.e two halves are same i.e identical</u> when it is reflected across an axis or line of symmetry.