it helps to give a detailed solution but actually, it is enough to derive a contradiction to the (appeared) diagram, such that the shown arrangement is in fact, impossible. this is easy: the overall triangle 5x13 and the blue triangle appear to be 2x5. however, it cant be true since the blue triangle is similar to the big traingle, yet 5:13 is not equal to 2:5

Posted by bal on 2002-04-30 17:57:41