If ` vec xa n d vec y`are two non-collinear vectors and a, b, andc represent the sides of a ` A B C`satisfying `(a-b) vec x+(b-c) vec y+(c-a)( vec xxx vec y)=0,`then ` A B C`is (where ` vec xxx vec y`is perpendicular to the plane of `xa n dy`)a. an acute-angled triangle b.an obtuse-angled trianglec. a right-angled triangle d. a scalene triangleA. an acute angled triangleB. ann obtuse angled triangleC. a right angled triangleD. a scalene triangle

If ` vec xa n d vec y`are two non-collinear vectors and a, b, andc rep

1.	If ` vec xa n d vec y`are two non-collinear vectors and a, b, andc represent the sides of a ` A B C`satisfying `(a-b) vec x+(b-c) vec y+(c-a)( vec xxx vec y)=0,`then ` A B C`is (where ` vec xxx vec y`is perpendicular to the plane of `xa n dy`)a. an acute-angled triangle b.an obtuse-angled trianglec. a right-angled triangle d. a scalene triangleA. an acute angled triangleB. ann obtuse angled triangleC. a right angled triangleD. a scalene triangle
Answer» Correct Answer - A As x,y and `x xxy` are non-collinear vectors, vectors are linearly independent. hence, `a-b=0=b-c=c-a` or a=b=c therefore, the triangle is equilateral.

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