Prove that a triangle with sides of length 5, 5 and 6 has the same area as a triangle with sides of length 5, 5 and 8. Find other pairs of non-congruent isosceles triangles which have equal areas.

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?

Add All the Angles

Age 11 to 14 Short Challenge Level:

Each letter in this diagram represents the angle between the two lines framing it.

What is the sum of all of the angles denoted by letters?