> Doesn't that factor to (x^2 - 9)(x^2 - 4)? -> x = +/-3, +/-2
Using "complex solutions" gives test takers making certain kinds of errors more rope to hang themselves with, although personally I consider something like x = +/- 3i, +/- 2i to be better than something like x = +/-9, +/-4, which in turn is better than something like x = +/-13, +/-36. Ideally, I'd want to see their work, but in the absence of that, for a total of 5 points for this problem, I might give 3 points for x = +/- 3i, +/- 2i and 1-2 points for x = +/-9, +/-4. Note that even x = +/-9, +/-4 suggests they correctly factored and they recognized there will be two pairs of solutions.