For the roots of a quadratic equation ax^2 + bx + c = 0 to be reciprocals, the product of the roots (c/a) must equal 1. Here, k/3 = 1, which implies k = 3.
For the roots of the quadratic equation 3x^2 - 14x + k = 0 to be reciprocals of each other, the condition is that the constant term equals the leading coefficient. This means k = 3.