In triangle ABC, BD and CE are the bisectors of angle B and angle C respectively. Given be = CD, it is proved that triangle ABC is isosceles triangle I'm sorry, but I can imagine everything

Proportional to the corresponding edge of the bisector, so
BC/CD=AB/AD,BC/BE=AC/AE
Because be = CD, AB / ad = AC / AE
So triangle ABC is similar to triangle ace
The angles corresponding to similar triangles are equal, so angle abd = angle ace
So angle ABC = angle ACB
It is proved that ~ triangle ABC is isosceles triangle

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