MathDB

14

Part of 1999 Baltic Way

Problems(1)

Area ratio is equal to length ratio

Source: Baltic Way 1999

12/23/2010
Let ABCABC be an isosceles triangle with AB=ACAB=AC. Points DD and EE lie on the sides ABAB and ACAC, respectively. The line passing through BB and parallel to ACAC meets the line DEDE at FF. The line passing through CC and parallel to ABAB meets the line DEDE at GG. Prove that [DBCG][FBCE]=ADDE\frac{[DBCG]}{[FBCE]}=\frac{AD}{DE}
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