 # Formulas for Perimeter and Area

## Presentation on theme: "Formulas for Perimeter and Area"— Presentation transcript:

Formulas for Perimeter and Area

PERIMETER OF A SQUARE P= 4s
Perimeter equals four times the length of one side

AREA OF A SQUARE A=s 2 Area of a square equals the length of one side squared (times itself)

3 in. Area of a Square A=s² A= 3 in. * 3 in. A=9 sq. in. 3 in. Perimeter of a Square P=4s P=4(3 in.) P=12 in.

PERIMETER OF A RECTANGLE P=2l+2w
Perimeter of a rectangle equals 2 times the length plus 2 times the width

AREA OF A RECTANGLE A=lw Area of a rectangle equals length times width

Perimeter of a Rectangle
P=2l+2w P=2(3 in.) + 2 (2in.) P=6 in. + 4 in. P=10 in. 3 in. 2 in. Area of a Rectangle A=lw A=3 in.(2 in.) A=6sq. in.

Find the perimeter and area of each figure.
Find the perimeter and area of each figure. Show all work! 4 cm 2.5 cm square 8 in. 11 in. 5 in. 7 in. 4 in. 4 in.

Now let’s try it when the measurement needs to change.
12 in. 12 in. We need the area in square feet. There are 2 methods 1. Convert first. 2. Convert after you have the area

Convert first. 12 inches = 1 ft Multiply 1 times 1 Area is 1 square foot. 12” 12 in.

Convert 2nd. 12” 12 times 12 = 144 square inches. 12” How many square inches are in a square foot? How man inches across the top? How many across the side? If we draw all of the boxes there will be 144 sq. inches in 1 square ft. We have divide square inches by 144 to get square feet!

24 in. What is the area in square feet? 18 inches

6 ft. Find area in square yards. 9 ft

100 cm. 250 cm. Find area in square meters. Hints: 100 cm = 1 meter 10,000 sq cm = 1 sq meter

Homework: problems below
Find the perimeter and area both in feet and yards for a rectangle with a length of 15 feet and a width of 9 feet. Find the perimeter & area of a square that has a side of 24 inches. Give your answer in both inches and feet. Find the perimeter and area of the following figure. 12 in. 9 in. 12 in. Don’t forget to show all work! 6 in.