Perimeter and Area

Perimeter: The perimeter of a shape is the total length of its boundary. It's like walking around the edge of the shape and adding up all the distances.

Formula for Perimeter: The formula for finding the perimeter (P) depends on the shape:

• • For a rectangle:   P =2×(length+width)

  • For a square:   P =4×side

  • For a triangle: P =side1+side2+side3 

  • And so on for other shapes.

Example:

• Consider a rectangle with a length of 5 units and a width of 3 units.

• Perimeter : P=2×(5+3)=16 units.

Area:  The area of a shape is the measure of the amount of space inside the shape. It's like finding out how much paint you'd need to cover the shape.

Formula for Area:

• Again, the formula depends on the shape:

  • For a rectangle:

  • �=length×width

  • A=length×width

  • For a square:

  • �=side×side

  • A=side×side

  • For a triangle:

  • �=12×base×height

  • A=

  • 2

  • 1

  • ​

  • ×base×height

  • And so on for other shapes.

Example:

• Take a square with each side measuring 4 units.

• Area

• �=4×4=16

• A=4×4=16 square units.

Key Points:

• Units:

  • Perimeter is measured in the same units as the sides (e.g., meters, centimeters).

  • Area is measured in square units (e.g., square meters, square centimeters).

• Comparison:

  • Perimeter is about the length around the shape.

  • Area is about the space inside the shape.

• Visualizing:

  • Perimeter is like measuring the fence around your yard.

  • Area is like measuring the space your carpet covers in your room.

• Real-world Analogies:

  • Think of a rectangular garden. The perimeter is the length of the fence around it, and the area is the space the garden covers.