Find the value of k so that the line kx-5y=21 will contain the point (-2,-1).
Substitute the point, x=-2, y=-1, into the equation and solve for k to see
what k would have to be:
kx - 5y = 21
k(-2) - 5(-1) = 21
-2k + 5 = 21
-2k = 16
k = -8
So the line -8x - 5y = 21 contains the point (-2,-1).
Edwin