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A circle, since it has an infinite number of lines of symmetry
Octagon
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An isosceles triangle and a kite have only one line of symmetry.
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a circle.
A parallelogram
A circle, since it has an infinite number of lines of symmetry
An irregular quadrilateral.
The 2D shape which has one line of symmetry is the trapezium.
There is no such shape. A 2d shape with 5 sides and all equal angles must be a regular pentagon (or a 5-pointed star if you stretch the definition of "all angles"). And a regular pentagon - or star - has 5 lines of symmetry.
Octagon
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Impossible.
A closed wiggly line. or many irregular polygons such as scalene triangle, ordinary quadrilateral, trapezium (if not isosceles), etc.
An isosceles triangle and a kite have only one line of symmetry.