Tangrams may be used as tools to teach geometry.
Various basic geometric shapes called polygons can be formed from the tangram
pieces. These polygons include triangles, quadrilaterals, pentagons, and
hexagons.
Quadrilaterals are polygons with four sides. Below are
examples of polygons that may be formed using tangrams:
Square
Trapezoid
Rectangle
Parallelogram
A square is a quadrilateral where all of its
sides and all of its angles are equal. The angles are right angles, or 90
degrees. A Rectangle is a quadrilateral where all of its angles are equal,
or are right angles.
A trapezoid is a quadrilateral with a pair of
opposite sides being parallel. A parallelogram is a quadrilateral
with both pair of opposite sides being parallel. A rectangle is a special
type of parallelogram with four equal angles, or with four right angles. A
square is a special type of parallelogram and a special type of rectangle.
It is a parallelogram, and a rectangle with 4 equal sides and 4 equal angles.
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