What is area? The amount of space that a figure encloses The number of square units that covers a shape or figure. It is two-dimensional It is always answered in square units

Area of a square S is the side Area= side x side A= s x s

Find the area of a square using the formula To find the area of a square, multiply the side x side Area = side x side Area = 3 m x 3 m The area is 9 m2 3 m 3 m

Area of a rectangle b is the base h is the height Area= base x height A= b x h You may also see this as A = l x w (Area = length x width)

Find the area of the rectangle using the formula To find the area of a rectangle, multiply the length x width. Area= length x width The length= 6 m The width=2 m Area=6 x 2 The area is 12 m2 6 m 2 m

Area of a triangle B is the base H is the height Area= ½ x base x height A= ½ x b x h

Find the area of the triangle using the formula Area = 1/2 x base x height A= 1/2 x b x h A= 1/2 x 8 x 5m A= 1/2 x 40 square meters A= 20 square meters The area is 20 m2 5 m 8 m

Area of a parallelogram Do Re Mi b is the base h is the height Area= base x height A= b x h

Find the area of parallelogram using the formula Area = base x height A= b x h A= 4 x 3 A= 12 square units The area is 12 units2

What is the area of this figure? It is a square Formula for the area of a square is side x side Side= 17 m Area= 17 x 17 A= 289 m2 17 m. 17 m

What is the area of this figure? It is a triangle Formula for the area of a triangle is A = ½ x base x height 4 cm 13 cm Base= 13 cm Side= 4 cm Area= ½ x 13 x 4 A= 26 cm2

What is the area of this figure? It is a parallelogram Formula for the area of a parallelogram is A = base x height Base= 3 units Height= 6 units Area= 6 x 3 A= 18 units2

What is the area of this figure? It is a rectangle Formula for the area of a rectangle is length x width Length= 8m Width= 3 m Area= 8 x 3 A=24 m2 8 m 3 m

What is the area of this figure? It is a square Formula for the area of a square is side x side Side= 12 cm Area= 12 x 12 A= 144cm2 12 cm 12 cm

What is the area of this figure? It is a triangle Formula for the area of a triangle is ½ x base x height Base= 8 m Side= 5 m Area= ½ x 8m x 5 m A=20 m2 5 m 8 m

What is the area of this figure? It is a parallelogram Formula for the area of a parallelogram is A = base x height Base= 5 units Height= 5 units Area= 5 x 5 A= 25 units2

What is the area of this figure? It is a rectangle Formula for the area of a rectangle is A = length x width Length= 13 cm Width= 4 cm Area= 13 x 4 A= 52 cm2 13 cm 4 cm

What is the area of this figure? 7 cm It is a rectangle Formula for the area of a rectangle is A = length x width Length= 16 cm Width= 7 cm 16 cm Area= 16 x 7 A= 112 cm2

Do you remember the formula for the area of a circle? For a circle, the area is: A = Πr2 = Π x 52 =78.54 cm2

What about unusual / composite shapes? This shape can be divided into two rectangles. Find their areas and add them together. Area 2= l x b = 4 x 6 = 24 cm2 Area 1= l x b = 8 x 20 = 160 cm2 Total area = A1 + A2 = 160 + 24 =184 cm2

In this case, a measurement needs to be found before you begin. Try another one: In this case, a measurement needs to be found before you begin. 7 m A2 = 15 x 7 =105 cm2 A1 = 5 x 8 =40cm2 Total area = A1 + A2 = 40 + 105 = 145 cm2

What did you learn? What is area? How are the units of area usually expressed? How many dimensions is area? What does the “S” mean in the formula for the area of a square? What is the formula for the area of a square? What is the formula for the area of a rectangle? What does the “h” stand for in the formula for the area of a triangle?

More… What is the formula for the area of a parallelogram? What does the “b” stand for in the formula for the area of a triangle? What does the “h” stand for in the formula for the area of a rectangle? What is the formula for the area of a rectangle? What are the four formulas we have learned today?

Closure: Remember Formulas! Square: A = s x s Rectangle : A = b x h Triangle: A = ½ x b x h Parallelogram: A= b x h Circle: A = π x r2

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