The process of getting your angles right is lengthy and boring. Snežana Jeremić has come up with a solution to “rule out” all of our angular problems.
‘ZigZag’ is a regular ruler, until you go to actually use it. Then, it’s your best friend in the dangerous world of trigonometry. Attempting to draw triangles usually requires a triangle ruler, but the downside to that method is the fixed angle. The ZigZag ruler combines the triangle, protractor, and traditional ruler to achieve a variety of commonly used angles. Simply place one end of the ruler into one of the various predefined slots to get the angle you need.