Perimeter and Area Formulas

Perimeter and Area

Finding Perimeter

• Perimeter is the distance around a shape
• Formula: P = 2(l + w) for rectangles and squares
• Formula: P = a + b + c + ... for polygons (where a, b, c are sides)
• Irregular shapes: break into smaller rectangles and triangles, calculate perimeter of each, and add

Calculating Area

• Area is the amount of space inside a shape
• Formula: A = lw for rectangles and squares
• Formula: A = (b * h) / 2 for triangles
• Formula: A = πr^2 for circles
• Composite shapes: break into smaller shapes, calculate area of each, and add

Real-world Applications

• Architecture: designing buildings, rooms, and spaces
• Engineering: calculating stress and load on structures
• Science: measuring habitats, territories, and populations
• Everyday life: measuring rooms, furniture, and carpets

Shape Properties

• Regular polygons: all sides and angles equal
• Irregular polygons: sides and angles not equal
• Congruent shapes: same size and shape
• Similar shapes: same shape, different size
• Symmetry: line or point of symmetry

Unit Conversion

• Length: convert between units (e.g., inches to feet, meters to centimeters)
• Area: convert between units (e.g., square feet to square meters)
• Common conversions:
  • 1 foot = 12 inches
  • 1 meter = 100 centimeters
  • 1 square foot = 0.0929 square meters

Perimeter and Area

Finding Perimeter

• Perimeter is the distance around a shape
• Formula for rectangles and squares: P = 2(l + w)
• Formula for polygons: P = a + b + c + ... (where a, b, c are sides)
• Irregular shapes: break into smaller rectangles and triangles, calculate perimeter of each, and add

Calculating Area

• Area is the amount of space inside a shape
• Formula for rectangles and squares: A = lw
• Formula for triangles: A = (b * h) / 2
• Formula for circles: A = πr^2
• Composite shapes: break into smaller shapes, calculate area of each, and add

Real-world Applications

• Architecture: designing buildings, rooms, and spaces
• Engineering: calculating stress and load on structures
• Science: measuring habitats, territories, and populations
• Everyday life: measuring rooms, furniture, and carpets

Shape Properties

• Regular polygons: all sides and angles equal
• Irregular polygons: sides and angles not equal
• Congruent shapes: same size and shape
• Similar shapes: same shape, different size
• Symmetry: line or point of symmetry

Unit Conversion

• Length: 1 foot = 12 inches, 1 meter = 100 centimeters
• Area: 1 square foot = 0.0929 square meters
• Need to convert between units when working with different measurement systems