Consider the rectangular prism with length 5 in., width 8 in., and height 9 in.

Will tripling one of the dimensions of the rectangular prism triple the surface area of the prism? Justify your response.

No, the only thing it would triple is the area of some of the sides. If you tripled 5 for example the new SA would be 654. That is not 314 tripled.

But it would triple the area of the two bases that length 8 and width 5 have. However tripling one dimension only affects two things, the two areas it makes with either the width, length, or height