Answer:
The length of the longer side is 12 in
Explanation:
Scaling
The dimensions of the photographic negative are 2 in by 1.5 in.
An enlarged print of it has a length of 9 in and it's equivalent to the shortest side.
Since the shortest side of the negative is 1.5 in, the scale factor is 9/1.5 = 6.
The longer side should have been enlarged by the same factor, thus the longer side is 2*6 = 12 in
The length of the longer side is 12 in