Area and Surface Area

Area and Surface Area

Area

• The number of square units needed to cover the surface of a closed figure

• Area of a rectangle: A = lw

• Expressed as units squared

Find the area of a rectangle

Multiple Choice

Find the Area of the Rectangle.

• 160 feet

• 160 feet squared

Surface Area of a Rectangular Prism

• The total area of all 6 faces

• SA = 2lw + 2lh + 2wh

• Expressed in units squared

Let's look at its Net

• A rectangular prism has 6 faces

• Each face has a "twin"

• 2 pink and 2 blue and 2 orange

• 2lw + 2lh + 2wh

Find the surface area of the rectangular prism

1. Label diagram

2. Write correct formula

3. Substitute

4. Solve

5. Unit of measure

Multiple Choice

Step 1: Label length, width, and height. What is the height of this figure?

• 6 in.

• 12 in.

• 15 in.

Multiple Choice

Step 2: Choose the correct formula. Which formula should we use to calculate the surface area?

• A = lw

• SA = 2lw + 2lh + 2wh

Multiple Choice

Step 3: Substitute in your information. Which is correct?

• SA = 2x12x15 + 2x12x6 + 2x15x6

• SA = 2x12x15 - 2x12x6 - 2x15x6

Multiple Choice

Step4: Use order of operations to solve properly. Which is the correct order? SA = 2x12x15 + 2x12x6 + 2x15x6

• Add then Multiply

• Multiply then Add

• Solve the whole thing from left to right

• Order does not matter

Multiple Choice

SA = 2x12x15 + 2x12x6 + 2x15x6 Which could this simplify to?

• 360 + 144 + 180

• 21215 + 1126 + 2156

• 29 + 20 + 23

Multiple Choice

Step 5: Use the correct unit of measure. Which is the final answer?

• 684 units

• 684 units squared

Multiple Choice

Area describes...

• The number of square units needed to cover the surface of a closed figure

• The total area of all 6 faces

Multiple Choice

Surface Area describes...

• The number of square units needed to cover the surface of a closed figure

• The total area of all 6 faces