Mathematics

Problem

\mathbf{x}

and

\mathbf{y}

are two non-collinear vectors and

a, b

and

c

represent the sides of a

\Delta ABC

satisfying

(a-b)\mathbf{x} + (b-c)\mathbf{y} + (c-a)(\mathbf{x} \times \mathbf{y}) = \mathbf{0}

, then

\Delta ABC

is (where

\mathbf{x} \times \mathbf{y}

is perpendicular to the plane of

\mathbf{x}

and

\mathbf{y}

) a. an acute angled triangle b. an obtuse angled triangle c. a right angled triangle d. a scalene triangle