In order for two polygons to be similar, two conditions must be met. First, all pairs of corresponding sides must be in proportion. Second, all corresponding angles must be congruent.
Prove that proportionality of sides is not enough, by itself, to establish that two polygons are similar. Do this by drawing two polygons that are not similar but whose sides are all in the same proportion.
Just imagine two polygons made out of pipe cleaners......and all of the sides are proprtional (or even the same length)....then you knda squoosh one to the side.....now it has equal length sides, but not angles and it doesn't look like the other....can you draw something like that?