Question 383752
Both have one pair of parallel sides, but by definition, a rectangle is NOT a trapezoid since a trapezoid can have ONLY one set of parallel sides and a rectangle always has two. this keeps it from 
actually being a rectangle 

A trapezoid is a quadrilateral having one pair of parallel sides.

Parallel sides of trapezoid are base sides and distance between parallel sides is height of trapezoid.

Area of trapezoid is given as product of average of base sides and height of trapezoid.

Area= 21(Sum of base sides) X height

A trapezoid is a quadrilateral having one pair of parallel sides.

Parallel sides of trapezoid are base sides and distance between parallel sides is height of trapezoid.

Area of trapezoid is given as product of average of base sides and height of trapezoid.

Area= 21(Sum of base sides) X height

Here A, B, C and D are four vertices of trapezoid. AB and CD are parallel sides and BC and DA are non-parallel sides. Length AB is ‘a’ and that of CD is ‘b’.

Area= 21 (a + b)h



Properties of Trapezoid
1. It must have four sides, four corners and two diagonal.

2. The sum of interior angles is 360 degrees.

3. Angle adjacent to opposite bases are supplementary.



4. It has one pair of parallel sides.

5. It has median(line equidistant from parallel sides) whose length is given as \frac12 X Sum of parallel sides.

6. length of any line parallel to parallel sides can be calculated as-

    EF is parallel to AB

    EF = [kX(CD)]+[mX(AB)](AD)


Isosceles trapezoid
If the two non-parallel sides have equal lengths, then the trapezoid is called an isosceles trapezoid.

Properties of Isosceles trapezoid

 1. Isosceles trapezoid has exactly one line of symmetry and that is the line joining mid-point of parallel sides. So, basically this line is dividing it again into two trapezoids.




 2. Base angles of isosceles trapezoid have same measure.

     Here If 1 and  2 are base angles.

     So, If 1 =  2

     And also angle DAB =angle  DCB



 3. Opposite angles are supplementary.

 4. The diagonals of trapezoid have same length.

 5. On the extension of non-parallel side isosceles triangle is formed.