You can. Go to your text message app. Then go to someone you've been texting, or you can click that little pencil in the top right of the screen and choose a contact to text to. Do you see where you're supposed to type your text messages at? It's a little rectangular box. In front of that box should be a tiny picture of a camera. Click the tiny picture. It should give you two options: to take a picture, or choose a picture from your gallery. If you want to take a picture just take one, and it'll pop right up once you say you want to use it. If you want to choose from gallery it'll take you to your photo gallery. Then you scroll up or down wherever the picture you want to send is at and click that picture. It will then pop up on your text box. Just click send which is a circle button to the right of the text box. And you've sent your first picture! (If your issue is trouble with the picture sending and it keeps saying failure take it to AT&T. They can fix it)
for all those who are being smart asses (or ignorant), my guess would be to say that the person who posted this meant that they know how to send it but when they do they get a issue saying failure to send.