You will still probably have the tip when you cut. How wide is the ruler you bought? If you are following the book, your strips are 3.75 inches. Most rulers (triangles) have horizontal lines on them so that you can align it with different size strips. If your ruler is taller (wider?) than 3.75 inches, then you will line it up and when you cut, you will still have your points, which are indeed needed when piecing the triangles.