1. Chapter 1.7 Notes: Find Perimeter, Circumference, and Area

2. Perimeter is the distance around a figure.
Circumference is the distance around a circle.
Area is the amount of surface covered by a figure.
Perimeter and circumference are measured in units of length, such as meters (m) and feet (ft).
Area is measured in square units, such as square meters (m2) and square feet (ft2).

3. Formulas for Perimeter, Area, and Circumference: Square: Area (A) = s2
Perimeter (P) = 4s
Area (A) = s2
(s = side length)
Rectangle:
Perimeter (P) = 2L + 2w
Area (A) = Lw
( L = length, w = width)

4. (for perimeter; side lengths of triangle a, b, c)
Perimeter (P) = a + b + c a b
Area (A) = ½ bh
(for perimeter; side lengths of triangle a, b, c)
(for area; b = base, h = height)
Circle:
Circumference ( C) = πd or C = 2πr
Area (A) = πr2
Pi (π) is the ratio of a circle’s circumference to its diameter.

5. Ex.2: Find the perimeter and area of the dining room shown. 12 ft
Ex.1: Find the perimeter and area of the rectangular basketball court shown.
Ex.2: Find the perimeter and area of the dining room shown ft
9 ft

6. Ex.3: You are ordering circular cloth patches for your soccer team’s uniforms. Find the approximate circumference and area of the patch shown. Ex.4: Find the approximate circumference and area of the circular window shown. (d = 18 in)

7. Find the area and perimeter of the figure
Find the area and perimeter of the figure. If necessary, round to the nearest tenth.
Ex.5:
1.6 cm
Ex.6: Triangle QRS has vertices Q(1, 2), R(4, 6), and S(5, 2). What is the approximate perimeter of triangle QRS?

8. Ex. 7: Use the diagram below to answer (a) and (b). a
Ex.7: Use the diagram below to answer (a) and (b). a. Describe how to find the height from F to EG in the triangle below. b. Find the perimeter and the area of the triangle shown below.

9. Ex. 8: The base of a triangle is 28 meters
Ex.8: The base of a triangle is 28 meters. Its area is 308 square meters. Find the height of the triangle. Ex.9: The base of a triangle is 14 cm. Its area is 42 cm2. Find the height of the triangle.

10. Ex.10: An ice-resurfacing machine is used to smooth the surface of the ice at a skating rink. The machine can resurface about 270 square yards of ice in one minute. About how many minutes does it take the machine to resurface a rectangular skating rink that is 200 feet long and 90 feet wide?