Area = Length * Width. Let's assume not a square and height means width. Length can be 5'' for the arguments sake.
A = 5" * 3'' = 15 in^2
A = 5'' * 9'' = 45 in^2
45/15 = 3 times as large in this instance
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A = 5" * 3'' = 15 in^2
A = 5'' * 9'' = 45 in^2
45/15 = 3 times as large in this instance
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