Finding Area of Rectilinear Shape

Area and Perimeter

Area

• Area is the number of square units that covers the inside of a shape.

• We can use the formulae L * W to find the area of a square or rectangle.

Multiple Choice

What is the area of a rectangle that has a length of 8 feet and a width of 6 feet?

• 14 squared feet

• 40 squared feet

• 48 squared feet

• 15 squared feet

To find the area of rectilinear shapes do the following steps:

• Decompose (cut) the shape into squares or rectangles

• Find the area of each square/rectangle by multiplying the length and width.

• Add all the areas together..... OR

• Draw the rectilinear shape on your grid paper using the correct measurements given, then count the square units inside the shape.

Multiple Choice

What is the area of this shape?

• 50cm squared

• 80 cm squared

• 44cm squared

• 28cm squared

Perimeter

• Perimeter is the distance around the shape

• To find the perimeter of a shape, add all the sides around the shape.

Multiple Choice

What is the perimeter of a rectangle that has a length of 8 and a width of 6?

• 14

• 48

• 24

• 28

Multiple Choice

Which measurement below has a perimeter of 18?

• Length = 7; Width = 7

• Length = 10; Width = 8

• length = 2; width = 9

• length = 2; width = 7

How can I find the missing side if the perimeter or area is given?

• Read the problem carefully

• Write down the information that is given.

• Use your knowledge of how to find the area and perimeter to help you solve for the missing side.

Multiple Choice

The perimeter of a shape is 26 cm. The width is 9cm. What is the length?

• 4

• 8

• 26

• 9

Multiple Choice

The area of a shape is 36. The length is 12. What is the width of the shape?

• 4

• 24

• 3

• 36