Let us have four distinct collinear points A,B,C and D on the Cartesian plane. The point C is such that AB/CB = 1/2 and the point D is such that DA/BA = 3 and DB/BA = 4. If C = (0,4), D = (4,0) and A = (x,y), what is the value of 2x + y?
2x + y = -4/7.
