Visual Surface Area: Intuitive Introduction

This applet shows a rectangular prism.[br]We can change the dimensions and create the net. [br]The net allows us to visualize and determine the surface area.[br]Play with the applet for a bit and answer the questions below.

How many rectangles are shown in the net?

OPTIONS slider

Play with the OPTIONS slider. What happens each time? Explain

SURFACE AREA

The surface area is the sum of the areas of all the faces (rectangles).[br]Set the length=6, width = 5 and height = 4 and let's assume the units are cm.[br]Show how you calculate the surface area of the prism.[br][i][br]Hint: Consider using the net or the OPTIONS sliders to help you visualize.[/i]

Checking

Four students calculated the surface area of a rectangular prism with dimensions 6cm X 5cm X 4cm.[br][br]Which of the following calculations do you prefer?

[math]2\left(24+30+20\right)=148cm^2[/math] [math]2\left(6\cdot4+6\cdot5+4\cdot5\right)=148cm^2[/math] [math]2\left(6\cdot4\right)+2\left(6\cdot5\right)+2\left(4\cdot5\right)=148cm^2[/math]

Why did you select this answer? Explain.

Determine the surface area of a prism with length = 9m, width = 6m and height = 3m

Visual Surface Area: Intuitive Introduction

How many rectangles are shown in the net?

OPTIONS slider

SURFACE AREA

Checking

Information: Visual Surface Area: Intuitive Introduction