Move content on one page to another page

Hello:

I have one side of a postcard on page 1 in a pdf file, and the other side of the postcard on page 2 in the same pdf file. Now, there is space on page 1 for the postcard side on page 2. Is there any way I can move the content of page 2 to the bottom of page 1 in order to get the postcard on only one pdf page?

Thanks,

Hans L