Ok so it's a proportion so this fraction is to this fraction. the smaller rectangle has sides 4 and 12. the larger one has 8 and x. so u set it up 4/12=8/x. the 4 and 8 r both the short sides so u want those on top and 12 and x r long sides so those on bottom. since that is not an answer option u can set it up as 8/4=x/12 because u still keep the variables of the same rectangle from being multipled with each other. so answer #2 is correct
What you have highlighted right now is correct. Because the rectangles are similar (proportional): l of rect 1 / l of rect 2 = w of rect 1 / w of rect 2
