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A polygon is a 2D closed figure with straight sides.
Sheet
In a regular polygon, the sides are all the same length and all angles are the same size.
equilateral square regular regular regular
triangle pentagon hexagon octagon
. k
A triangle is a polygon
with three sides.
scalene triangle equilateral triangle isosceles triangle
A quadrilateral is a polygon with four sides.
square rectangle parallelogram rhombus trapezium kite
A solid is a 3D object. It has 3 dimensions: height, width and depth.
7^
§
cube (square cuboid triangular cylinder pentagonal square cone sphere
prism) (rectangular prism prism pyramid
prism)
Some solids have faces, edges and vertices. A sphere has no faces, edges or vertices.
9
vertex
edge
A line of symmetry cuts a shape Into two equal parts that mirror each other.
The dotted line is an axis of The dotted line is not an axis of
symmetry of the semicircle. symmetry of the quadrilateral.
The order of rotation symmetry is the number of times a shape fits onto itself in one full turn.
This shape has 6 lines of symmetry.
It will fit onto itself 6 times when rotated.
Its order of rotation symmetry about its centre is 6.
