(x's Square - 4x + 4) / (2x-6) / (x's square + X-6) / (12-4x) × (x + 3) / (1)

(x's Square - 4x + 4) / (2x-6) / (x's square + X-6) / (12-4x) × (x + 3) / (1)

=2(x-3)/(x-2)²×(x+3)(x-2)/-4(x-3)×1/(x+3)
=-1/2(x-2)
=-1/(2x-4)