<Tri-2024-2164>, hint
Let <A=90, inradii of triangles ABD and ACD be r and r' respectively
In triangle <EDF=90, DE/DF=r/r'=AB/AC and so triangles BAC and EDF are similar
Hence <ABC=<DEF=<DAC ,so E, D, L, A are concyclic ---> <ALE=<ALK=<ADE=45
Since <A=90 <AKL=90-45=45. Triangle AKL is isosceles. AK=AL.
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