10.1. PolygonsA polygon: A two dimensional shape that is
enclosed by straight lines on all its sides.The number of vertices
= the number of sides.The number of diagonals = n (n 3), where n is
the number of sides
For example: ABCD is a polygon with four sides, AB, BC, CD and
DA.The vertices A, B, C and D are written in capital
letters.Diagonals: lines that join two non-adjacent vertices, AC
and BD.ADCBsidevertexdiagonal
A polygon is named according to the number of sides.
10.2. SymmetryA shape is said to have a line of symmetry if it
is can be divided equally so that one half overlaps exactly onto
the other.The line of symmetry is also known as the axis of
symmetry.E.g.: line/axis of symmetry
10.3. TrianglesA triangle: A polygon which has three sides.An
equilateral triangle has 3 lines of symmetry.
