As shown in the figure, in the triangle ABC, the angle a = 60 degrees. The bisectors BD and CE of the triangle ABC intersect at point F. if be = 4 and CD = 2, find the length of BC
As shown in the figure, ∠ CDB = 60 °+ ∠ B / 2. & nbsp; ∠ CEB = 60 °+ ∠ C / 2. & nbsp; ∠ B + ∠ C = 120 °. ℅ CDB + ∠ CEB = 120 °+ 120 ° / 2 = 180 °. Take g ∈ BC, so ∠ FGB = ∠ Feb. & nbsp; thus ∠ FGC = 180 °- ∠ FGB = 180 °- ∠ Feb = ⊿ CDF ⊿ FBG ≌ FBE, ≌ FCG ≌ FCD
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