Yes, it is common practice in the acting industry to print an actor's resume on the back of their headshot. This is known as a "resume shot" or a "headshot resume." It is a convenient and efficient way to present both your headshot and your resume together, and it is a standard format that many casting directors and agents are used to seeing. However, make sure that the printing quality is good and the text is legible. Additionally, it is still a good idea to have a separate digital copy of your resume to send out electronically when needed.