For what values of $‘k’$ will the pair of equations $3x + 4y =12$ and $kx + 12y = 30$ $NOT$ have a unique solution?
Option A. 9
To not have a unique solution, lines should be parallel.
Two parallel lines have equal slopes.
Slope of the line 3x+4y = 12, = -3/4
Slope of the line kx+12y = 30, = -k/12
3/4 = k/12 or k=9