A square with the sides measuring cm is divided into three triangles. Which of the following statements is certainly true?
Pick one
Solution
There are only three essentially different ways of dividing a square into three triangles:
both cuts run from a vertex to a common point on one of the sides.
Notice that in all three cases the area of the biggest of the three triangles is . The counterexamples for the statements A, C, D and E are ▱A, ▱B and ▱C respectively.
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