Formulas
Finding the Perimeter
Finding the Area
Let's Multiply!
Let's Problem Solve!
100
What is the formula for finding the perimeter of a shape?
s + s + s + s...
100
Find the perimeter: A square that has the length of 3 cm.
P = s + s + s + s OR s x 4
= 3 + 3 + 3 + 3 OR 3 x 4
= 12 cm
100
Find the area of a square: The width is 5 cm.
A = l x w
= 5 x 5
= 25 square cm
100
What's the area of this square?
Length: 9 mm
A = l x w
= 9 x 9
= 81 mm
100
Miss Steele wants to make a rectangular garden with an area of 24 square cm. How many different ways can Miss Steele make her garden? How do you know?
Miss Steele can make her garden 8 different ways. I know because I found all the possible number combinations that when multiplied together, equal 24.
1 x 24 24 x 1
2 x 12 12 x 2
3 x 8 8 x 3
4 x 6 6 x 4
200
How do we find the area of a rectangle?
A = l x w
200
Find the perimeter of a square: The length of a square is 10 m
P = s + s + s + s OR s x 4
= 10 + 10 + 10 + 10 OR 10 x 4
= 40 m
200
Find the area of a rectangle: The length is 9 cm and the width is 4 cm.
A = l x w
= 9 x 4
= 36 square cm
200
What's the area of this rectangle?
Length: 30 m Width: 12 m
A = l x w
= 30 x 12
= 360 square m
200
A diagonal of a parallelogram is drawn forming 2 triangles. If the area of one of the triangles is 16 square cm, what is the area of the parallelogram?
The area of the parallelogram is 32 square cm.
300
Which shape has the formula: A = b x h
Parallelogram
300
Find the perimeter of a rectangle: The length is 3 mm and the width is 2 mm.
P = s + s + s + s OR (2 x l) + (2 x w)
= 3 + 2 + 2 + 3 OR (2 x 3) + (2 x 2)
= 10 mm
300
Find the area of a parallelogram: The base is 12 m and the height is 5 m.
A = b x h
= 12 x 5
= 60 square m
300
What's the area of this rectangle?
Length: 24 cm Width: 18 cm
A = l x w
= 24 x 18
= 432 square cm
300
Mrs. Deren asks her students to construct a parallelogram with a perimeter of 24 square m and an area of 28 m.
Which dimensions are correct?
B = 8m H = 3m A = 6m
B = 6m H = 4m A = 5m
B = 7m H = 4m A = 7m
B = 7m H = 4m A = 5m
400
Which shape has the formula: A = (b x h) ÷ 2
Triangle 
400
Find the perimeter of a rectangle: The length is 9 cm and the width is 5 cm.
P = s + s + s + s OR (2 x l) + (2 x w)
= 9 + 5 + 5 + 9 OR (2 x 9) + (2 x 5)
= 45 cm
400
Find the area of a parallelogram: The base is 5 mm and the height is 105 mm.
A = b x h
= 5 x 105
= 525 square mm
400
What's the area of this parallelogram?
Base: 36 cm Height: 14 cm
A = b x h
= 36 x 14
= 504 square cm
400
Miss Steele wants to draw a parallelogram AND a triangle with an area of 28 square m. Show your work.
Parallelogram Triangle
A = b x h A = (b x h) ÷ 2
= 7 x 4 = (7 x 8) ÷ 2
= 28 square m = 56 ÷ 2
= 28 square m
500
When you see 1/2 in a formula, what does it mean you should do?
Divide by 2!
500
What is the perimeter of the following shape? (Show your work)
P = s + s + s + s + s
= 9 + 5 + 4 + 6 + 8
= 32 m
500
Find the area of a triangle: The base is 8 cm and the height is 6 cm.
A = (b x h) ÷ 2
= (8 x 6) ÷ 2
= 48 ÷ 2
= 24 square cm
500
What's the area of this parallelogram?
Base: 135 m Height: 26 m
A = b x h
= 135 x 26
= 3510 square m
500
What is the total area of the shaded region in this diagram?
Length = 5 cm Width = 8 cm
A = l x w
= 5 x 8
= 40 square cm
Area of shaded region = 40 ÷ 2
= 20 square cm