Question
Let S denote the locus of the point of intersection of the pair of lines 4 x-3 y=12 4 x+3 y=12 where varies over the set of non-zero real numbers. Let T be the tangent to S passing through the points (p, 0) and (0, q), q>0, and parallel to the line 4 x- 3 2 y=0. Then the value of p q is