Area and perimeter of parallelograms

Topic Notes

In this lesson, we will learn:

  • The basic properties of the shape of the parallelogram
  • How to understand and calculate the perimeter of a parallelogram
  • How to understand and calculate the area of a parallelogram

Notes:

  • A parallelogram is a 2D shape with 4 straight sides
    • Each pair of sides (across from each other) are parallel and the same length
    • The internal angles are not right angles (90°); otherwise it would be a rectangle
      • Opposite angles are the same size

2D Shapes: Area and Perimeter of Parallelograms

    • A special parallelogram with all sides of equal length is called a rhombus

2D Shapes: Area and Perimeter of Parallelograms

  • The perimeter is the exact distance around the shape.
    • Perimeter is a 1D (one-dimensional) quantity
      • It uses units such as meters (m, cm, mm, km), miles (mi), yards (yd), or inches and feet (in and ft)

    • For parallelograms, the formula is written as:
      • Pparallelogram = (2×a)+(2×b) ( 2 \, \times \,a) \, + \, (2\, \times \, b)
        • Where aa is the length of one of the sides, and bb is the length of the other side

  • The area is the space that is covered by the shape.
    • Area is a 2D (two-dimensional) quantity
      • It uses squared units such as square meters (m2, cm2, mm2, km2), square miles (mi2), square yards (yd2), or square inches and feet (in2 and ft2)

    • For parallelograms, the formula is written as:
      • Aparallelogram = b×h b \, \times \, h
        • Where bb is base, and hh is height

    • A parallelogram’s height is not the same as the slant (side) length.

2D Shapes: Area and Perimeter of Parallelograms