If the equations of the sides of a triangle are x + y = 2, y = x and 3y+x=0, then which of the following is an exterior point of the triangle?

The lines y = x and 3y+x=0, are inclined at 450 and 1500, respectively, with the positive direction of x-axis. So, the angle between the two lines is an obtuse angle. Therefore, orthocentre lies outside the given triangle, whereas incentre and centroid lie within the triangle (In any triangle, the centroid and the incentre lie within the triangle).