2007 National, Junior 11
Posted: Sun Jan 27, 2013 1:06 am
If $a,b,c$ are the sides of a triangle such that $a^2+b^2+c^2=ab+bc+ca$. Prove that the triangle is equilateral.
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This problem is also a problem of BdMO National 2008 Junior!Fahim Shahriar wrote: ↑Sun Jan 27, 2013 1:06 amIf $a,b,c$ are the sides of a triangle such that $a^2+b^2+c^2=ab+bc+ca$. Prove that the triangle is equilateral.