Теория:

Isosceles trapezium: 
  • An Isosceles trapezium is a type of trapezium where the non-parallel sides are equal in length.
  • Opposite angles are not equal.
  • Diagonals are equal.
  • Adjacent angles are equal.
Isosceles-trapezoid.png
  
Scalene trapezium:
  • A scalene trapezium is a trapezium with no sides of equal measure.
  • Opposite angles are not equal.
  • Diagonals are unequal.
  • Adjacent angles are unequal.
     
    scalane trapezium.jpg