Presentation on theme: "Understanding Perimeter and Area"— Presentation transcript:
1 Understanding Perimeter and Area GeometryMr. ZampettiUnit 5, Day 1
2 ObjectiveTo be able to find the area and perimeter of squares and rectangles
3 Work Together Get into groups of 3. Everyone needs ½ piece of graph paper.Each person in the group should complete one of the following:A rectangle with length 5 units and width 3 unitsA rectangle with length 8 units and width 2 unitsA rectangle with each side 4 units.
4 Work Together Record the perimeter of each rectangle Are the rectangles with equal perimeters congruent, similar, or neither?Record the area of each rectangle.Are the rectangles with the same area congruent, similar, or neither?Do the rectangles with equal perimeters have the same area?
5 DefinitionPerimeter – the sum of the lengths of the sides
6 Perimeter of a Rectangle P = 2b + 2h OR P = 2(b+h)bhhb
9 Find the PerimeterIf one side of a square is 6, what is the perimeter?24
10 DefinitionArea – the number of square units enclosed by the polygon
11 Postulate 5-1The area of a square is the square of the length of a side.A = s2If the side of a square is 5, what is the area?25
12 Try This: What is the area of a square whose sides are 12 in. long? What is the area of a square whose sides are 1 ft long?How many square inches are in a square foot?
13 Postulate 5-2If two figures are congruent, their areas are equal
14 Theorem 5-1: Area of a Rectangle The area of a rectangle is the product of its base and heightA = bhTo find the area, you must use the same units for all dimensions!!!bh
15 Real World ExamplesYou are designing a rectangular banner that will be 2 yd long and 4 ft wide. How much material would you need?You are making a sign with the length 75cm and width 2m. What is the area?
16 Find the Perimeter and Area to the following: Perimeter = 32in Area = 51in2
17 HomeworkWork Packet:Understanding Perimeter and Area