The obtuse angle (bottom) really stretches the curve backwards. The angled vertical axis and horizontal one are of equal lengths. Each of the 3 triangle versions have all 3 sides connected to each other. The top left triangle is a rounded version sketched to encompass the original shape. Right, acute, obtuse angle lines offer the potential of numerous parabolic line configurations. Once the procedural rules are understood, we're ready to apply them in new concepts.