H is height, and A is area. You are trying to figure out the length, width, and volume. To find the volume to H x A which is 5 1/4 x 12. 63 is the volume. To find the length and the width you must find (blank) x (blank) = 12. That could be 3 x 4, or 6 x 2. So your dimensions are
Height = 5 1/4
Width = 3 (or 4)
Length = 4 (or 3)
Area = 12
Volume = 63
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Another answer is:
Height = 5 1/4
Width = 2 (or 6)
Length = 6 (or 2)
Area = 12
Volume = 63
Hope this helps :)
