Perimeter Area S Small What is Perimeter Mathematics

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Perimeter & Area S. Small

Perimeter & Area S. Small

What is Perimeter • Mathematics for CSEC by S. Chandler, E. Smith, F. Ali,

What is Perimeter • Mathematics for CSEC by S. Chandler, E. Smith, F. Ali, C. Layne & A. Mothsersill • The perimeter is the length of the line enclosing a region of a surface.

Perimeter A D Perimeter = A + B + C +D B C

Perimeter A D Perimeter = A + B + C +D B C

Perimeter - Rectangle A D Perimeter = A + B + C +D B

Perimeter - Rectangle A D Perimeter = A + B + C +D B C

Area – Sqaure & Rectangle A D Area = L * W Area =

Area – Sqaure & Rectangle A D Area = L * W Area = A * B or C * D B C

What is a polygon? • A shape that has many sides Mathematics for CSEC

What is a polygon? • A shape that has many sides Mathematics for CSEC by S. Chandler, E. Smith, F. Ali, C. Layne & A. Mothsersill

Polygons

Polygons

How do you find the perimeter and area of a polygon? • Add the

How do you find the perimeter and area of a polygon? • Add the length of each side. • Find the area of the familiar shapes. Then add those areas together.

Find the area of an irregular figure • Divide the figure into regular shapes

Find the area of an irregular figure • Divide the figure into regular shapes • Look for the missing measurements that you would need to find the area of each regular figure. • Find the area of every regular figure • Add the areas of each regular figure together to find the total area.

Divide irregular figure into regular figure

Divide irregular figure into regular figure

Look for the missing measurements that you would need to area of each regular

Look for the missing measurements that you would need to area of each regular figure.

Find the area of every regular figure B B

Find the area of every regular figure B B

Add the areas of each regular figure together to find the total area. •

Add the areas of each regular figure together to find the total area. • A = 16 m 2 • B = 40 m 2 • Total = A + B = 16 + 40 = 56 m 2

Find the perimeter and Area of the following shape

Find the perimeter and Area of the following shape

Perimeter of a triangle? Perimeter = 5 + 9 + 11 = 25 cm

Perimeter of a triangle? Perimeter = 5 + 9 + 11 = 25 cm

Perimeter of a triangle Perimeter = 4 + 4 = 12 cm

Perimeter of a triangle Perimeter = 4 + 4 = 12 cm

Area of a triangle Area = ½ × b × h b = base

Area of a triangle Area = ½ × b × h b = base h = vertical height

Example: Sam cuts grass at $0. 10 per square meter How much does Sam

Example: Sam cuts grass at $0. 10 per square meter How much does Sam earn cutting this area:

Let's break the area into two parts:

Let's break the area into two parts:

 • Part A is a square: • Area of A = a 2

• Part A is a square: • Area of A = a 2 = 20 m × 20 m = 400 m 2 • Part B is a triangle. Viewed sideways it has a base of 20 m and a height of 14 m. • Area of B = ½b × h = ½ × 20 m × 14 m = 140 m 2 • So the total area is: • Area = Area of A + Area of B = 400 m 2 + 140 m 2 = 540 m 2

How much does Sam Earn? • Sam earns $0. 10 per square meter •

How much does Sam Earn? • Sam earns $0. 10 per square meter • Sam earns = $0. 10 × 540 m 2 = $54

Exercise

Exercise

What is Perimeter •

What is Perimeter •

 • The mathematical constant Pi, sometimes written as Pi, is approximately equal to

• The mathematical constant Pi, sometimes written as Pi, is approximately equal to 3. 14159. . . • Each year, Pi Day is celebrated on March 14 by math enthusiasts around the world.

Amazing Fact about pi •

Amazing Fact about pi •

What is the formula to calculate the diameter •

What is the formula to calculate the diameter •

What is the radius, diameter, circumference & area of this circle.

What is the radius, diameter, circumference & area of this circle.

Find the area of the following shape

Find the area of the following shape

Perimeter

Perimeter

Solve the following

Solve the following

 • 1. The figures shown at right, not drawn to scale, represent the

• 1. The figures shown at right, not drawn to scale, represent the cross sections of • 2 circular pizzas. Both pizzas are equally thick and contains the same toppings. • (a) Is the medium pizza twice as large as the small pizza? Use calculations to support your answer. (5 marks) • (b) A medium pizza is cut into 3 equal parts, and each part is sold for $15. 95. A small pizza is sold for $12. 95. Which is the better buy? Use calculations to support your answer. (5 marks)