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