Thread: triangle with biggest area

Of the fllowing triangles given by the lenghts if their sides, which one has the greatest area?

[1] 5,12,12
[2] 5,12,13
[3] 5,12,14
[4] 5,12,15
[5] 5,12,16

It should be [B], the right triangle. Can you see why?

If you draw an acute triangle, a right triangle and an obtuse triangle with two fixed lengths, 12 and 5, look at whats happening to the area inside



maybe the picture is less confusing.