Determine the total shaded area of the 'kissing triangles'.
ABCDEFGH is a 3 by 3 by 3 cube. Point P is 1/3 along AB (that is AP : PB = 1 : 2), point Q is 1/3 along GH and point R is 1/3 along ED. What is the area of the triangle PQR?
Four rods, two of length a and two of length b, are linked to form a kite. The linkage is moveable so that the angles change. What is the maximum area of the kite?
You need to be systematic. Start with certain limitations (constraints) and exhaust all possibilities - try to justfy how you know there are no other triangles in this "category". Then extend your investigation to more categories.