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In a A B C , if a^2+b^2+c^2=a c+ 3 a b , then the triangle is

Options

  1. Aequilateral
  2. Bright angled and isosceles
  3. Cright angled and not isosceles
  4. DNone of the above

Correct answer

C. right angled and not isosceles

Step-by-step solution

We have, a^2+b^2+c^2=a c+ 3 a b aligned & a^2 4 +c^2-a c+ 3 a^2 4 +b^2- 3 a b=0 & ( a 2 -c )^2+ ( 3 a 2 -b )^2=0 aligned array ll & a 2 -c=0 and 3 2 a-b=0 & a=2 c and 3 a=2 b & a= 2 b 3 =2 c= & a= , b= 3 2 and c= 2 array Now, b^2+c^2= ( 3 2 )^2+ ( 2 )^2= 3 ^2 a + ^2 4 = ^2 b^2+c^2=a^2 Hence, the triangle is right angled but not isosceles.

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