I got the same exact question from someone else couple min earlier. Here you go:)
If the rectangle ABCD is similar to rectangle EFGH, side CD is proportional to the side
C. GH
The order of the letters in naming the rectangle gives us which sides are adjacent in rectangle and which sides correspond to the other rectangle.
1 = 27
2 = 27
3 = 27
4 = 27
5 = 126