Points A(2,1) and C(10,5) are fixed vertices of a triangular park. The third vertex B must lie on the straight line 3x+4y=20 such that ∠B is a right angle.
a. (i) Find all possible coordinates of B that satisfy the given condition.
b. (ii) For each position of B obtained in part (i), calculate the area of △ABC. Comment on whether the two areas are equal, giving reasons for your answer.