A trapezoid is a quadrilateral with only a set of parallel opposite sides. Parallel sides are called the bottom of a trapezoid, the longer bottom is called the bottom, and the shorter bottom is called the bottom. The other side is called waist, and the vertical part between the two bottoms is called trapezoidal height.
Trapezoidal properties:
1, the top and bottom of the trapezoid are parallel.
2. The center line of the trapezoid is parallel to the two bottoms, which is equal to half of the sum of the upper and lower bottoms.
3. The diagonal lines of the isosceles trapezoid are equal.
Extended data:
Classification of quadrangles;
1, convex quadrilateral
The four vertices are in the same plane, the opposite sides do not intersect and are in a straight line with one side, and the other sides are on the same side.
Parallelogram (including: ordinary parallelogram, rectangle, diamond, square).
Trapezoidal (including: common trapezoid, right-angled trapezoid, isosceles trapezoid).
The sum of the inner and outer angles of the convex quadrilateral is 360 degrees.
2. Concave quadrilateral
The four vertices of the concave quadrilateral are on the same plane, the opposite sides do not intersect and are in a straight line with one side, and some of the other sides are on different sides.
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