Combined set of interacting instruments

A combined set of interacting instruments for constructing and analyzing two dimensional mathematical figures, said combined set of interacting instruments consisting of

• a ruler, an adjustable triangle assemble with variable included angles, a compass and a protractor, and wherein;
• said ruler consists of an elongated strip of rigid or semi-rigid transparent material having a length of between about 12 and 18 inches (30.48 and 45.72 cms), a width of about 1 to 2 inches (2.54 and 5.08 cms) and a thickness of between about 1/16 and 3/16 inch (xx to xx cm) and said ruler defining a straight edge along each side of said width with inches of length marked on one side and centimeters indicated on the opposite side, a pivot point including a relatively sharp point extending through a generally middle portion of said ruler with a pointed end to fix said pivot point to a backing and a pair of parallel longitudinally extending selected guideways parallel with one of said straight edges and a third slotted guideway parallel to said pair of guideways but extending between said pivot point and one end of said ruler and a sliding positioning hole disposed in said third guideway for positioning a marking instrument that rotatable about said pivot point to act as a compass;
• a triangular assembly including two moveable elements for forming two sides of a triangle and each of said moveable elements having first and second ends with said two moveable elements pivotally connected together at one end of each of said moveable elements whereby said moveable elements are disposable in an end to end relationship with an included angle therebetween of up to 180° along one of said straight edges of said ruler and each of said moveable elements including a guide follower at an opposite end from said pivot connector between said moveable elements and said guide followers interacting with and permanently fixed within one of said two guideways in said ruler for forming a triangle with one side of said triangle formed by said straight edge of said rule;
• said protractor comprising a thin transparent sheet of rigid or semi-rigid plastic having a flat base portion and an arcuate upper portion with angular indications between 0 and 180° in said base portion and said upper portion of said protractor including a pair of guide followers at opposite ends of said base portion for fitting into said second of said pair of guideways for measuring the included angle between said ruler and each of said moveable elements;
• and
• both of each moveable elements including a longitudinally extending slot connected to said pivot connector between said moveable elements to shorten two sides of said triangle.