I could have drawn E here, I could have drawn E anywhere, but regardless of where you draw E, if you draw a line segment between A and E, you see that we've form a right triangle from A to E, to the point we had the perpendicular, so let me call this point right here F, you're always going to draw a right triangle assuming that E is different than F and if you will immediately see that you see that D has to be shorter than this orange length, because this orange length is the hypotenuse.