and 1 long side. lay the triangle on your work surface, so the long side is facing you, and take the lower right hand corner and fold it onto the lower left hand corner. then unfold. this will create a crease from the top point of the triangle to the middle of the long side.
now fold the long side of the triangle up, leaving a small bit of the top point of the triangle showing.
now fold the top point over the long edge, as to line up with the crease we made earlier.
now make a mountain fold alone that crease, which basically means just fold the paper on that crease.
now 