Are they similar or not

AB and EF are the first two letters of ABCD and EFGH respectively. Therefore, these two sides correspond and pair up. They are the horizontal sides
AB = 4
EF = 8
Divide the two values
AB/EF = 4/8 = 1/2 = 0.5
We will use this value later so keep it in mind.
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The sides AD and EH also pair up (and correspond). This is because the letters A & D are the first and last letters of ABCD. Same applies for E & H being the first and last letters of EFGH
AD = 2
EH = 6
Divide: AD/EH = 2/6 = 1/3 = 0.33 approx
Since we did not get 1/2 = 0.5 like we did above, this means that the sides are not in proportion to one another. Meaning that the rectangles are not similar.
So the equation AB/EF = AD/EH, which turns into 4/8 = 2/6, is not a true equation.
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