text/image alignment in a post

hi this is probably a really newbie html question but i would like to know how to publish an image in a post with the right side of the image as a margin for the text. i don’t know if its clear so i’m making a sheme here: (i want it to look like on Ex°1, not °2 which is default, i think you get the point)

Ex °1
—- texttext
—- texttext
—- texttext
texttexttextt

Ex °2
—-
—-
—- texttext
texttexttext

any help would be much appreciated
thanks:)
thomas