(B) as well... I agree with what

vshaunak@gmail.com said above

For 2 equations of line, we have 3 possible cases:

> 1 point intersect the 2 lines = 2 different slopes for the lines

> No intersection = Same slopes and different Y-interceptors

> Infinite number of interesections = Same slopes and same Y-interceptors

So, the question just asks us for which value of k, the slopes are equal.

o 3x+4y = 12

<=> y = -3/4 * x + 12

o kx+12y = 30

<=> y = -k/12 * x + 30/12

By equalizing the 2 slopes, we have:

-k/12 = -3/4

<=> k = 12*3/4 = 9