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i have 2 different images i'm trying to put in an image side by side to  use on a birthday invitation.  the first image is on a large canvas,  when i copy the layer of the other image and put it in the one with the  canvas, it is larger than the one that was already there.  The images  are basically the same size, and the transform tool won't work.  how do i  get them the same size?  Tks!