It can be either, though often it is the bottom.
scale factor
It is the side of an isolateral figure.
Multiply the length of the side by the length of the top or bottom.
Measure the length of a side in the first figure = L1. Measure the length of the corresponding side in the second figure = L2. Then, provided L1 and L2 are in the same units, the relevant ratio is L1/L2.
The depth is neither the length nor width. Length is the measurement from top to bottom, width is from side to side, and depth is from front to back.
scale factor
Multiply (the length of one side) by (the length of one side).
It is the side of an isolateral figure.
Often, but not always.
Hhj
Multiply the length of the side by the length of the top or bottom.
You cannot figure out the length of an octagon without a lot more information. Alternatively, you can measure the lengths of the sides.
Measure the length of a side in the first figure = L1. Measure the length of the corresponding side in the second figure = L2. Then, provided L1 and L2 are in the same units, the relevant ratio is L1/L2.
The depth is neither the length nor width. Length is the measurement from top to bottom, width is from side to side, and depth is from front to back.
length and height is the same thing it is the height from the bottom to the top of the figure and width is the measurement across and object
You divide the length of a side of the first figure by the length of the line in the same relative position in the second figure.
It can be used as a side length, which has many possibilities to figure with.