Octagon abcdefgh and its dilation, octagon a'b'c'd'e'f'g'h', are shown on the coordinate plane below: octagon abcdefgh with ordered pairs at a at 3, 1, at b 3, negative 1, c 1, negative 3, d negative 1, negative 3, e negative 3, negative 1, f negative 3, 1, g negative 1, 3, h 1, 3. octagon a prime b prime c prime d prime e prime f prime g prime h prime with ordered pairs a prime 6, 2, at b prime 6, negative 2, at c prime 2, negative 6, at d prime negative 2, negative 6, at e prime negative 6, negative 2, at f prime negative 6, 2, at g prime negative 2, 6, at h prime 2, 6 if the center of dilation is at the origin, by what scale factor was octagon abcdefgh dilated?