A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).
Which of the following statements about a parallelogram is not true?
the area of a parallelogram is base x height 

the perimeter of a parallelogram is the sum of the lengths of all sides 

a parallelogram is a quadrilateral 

opposite sides and adjacent angles are equal 