Question

The surface area of a rectangular prism is 150 cm². If all the sides are tripled, what will the new surface area be?

Answer 1

Hint: surface area is two-dimensional.

Answer 2

1) Surface Area = 2Lw + 2wh + 2Lh = 150cm²

where:
L = length
w = width
h = height

So, if you new sides are trippled:

Surface Area = 2(3L)(3w) + 2(3w)(3h) + 2(3L)(3h)
= 18Lw + 18wh + 18Lh

Set up the ratio of new surface area to old:

(18Lw + 18wh + 18Lh)/(2Lw + 2wh + 2Lh) = Area/150

and solve for Area.

Answer 3

I think its 1,800

Answer 4

i hope this helps.

Answer 5

So I just add all that stuff up?