What value (s) of k, where k is an interger, will allow each quadratic equation to be solved by factoring?

x² + kx = 8

The factored form of the equation x²+kx=8 would be (x+a) (x+b) = 0, with whatever values of a and b make the equation equivalent to x²+kx-8=0.

So we get k=a+b and ab = (-8).

Possible integer factors of - 8 are:

1,-8 or - 1,8, giving k = - 7 or 7 (where's the plus-or-minus?)

2,-4 (k=-2) or - 2,4 (k=2)

So possible values of k are - 7, - 2, 2, 7.