What happens to the surface area of a rectangular prism if you double one dimension? Let's create several examples and see if a pattern emerges.
Let's take a look at Karen's post.
My rectangular prism has sides of 8 units, 6 units, and 5 units. To find the total surface area of the prism, I have to find the area of each face of the prism. There are two faces that have an area of 8(5) = 40 units2, two that have an area of 6(5) = 30 units2, and two that have an area of 8(6) = 48 units2. Adding all the areas I get the surface area is 236 units2.
If the smallest side is doubled the dimensions would be 8 units, 6 units, and 10 units. There are two faces that have an area of 8(10) = 80 units2, two that have an area of 6(10) = 60 units2, and two that have an area of 8(6) = 48 units2. Adding all the areas I get the surface area is 376 units2.
The surface area increased by 140 units2 or a factor of about 1.6.
Now it's your turn.
Come up with a set of dimensions for a rectangular prism, and calculate its surface area.
Double one of the dimensions of your prism. List the new set of dimensions, and find the new surface area.
Describe how doubling one of the dimensions affects the surface area.
Look at your classmates' posts. Add a response to one of the posts stating any patterns you noticed in the calculations of all your classmates, and the effect of doubling on dimension on the surface area.
Use the discussion rubric to see how you will be graded.