Vector AB = (6 - 2, 6 - 5) = (4, 1)

Vector AC = (5 - 3, 9 - 5) = (2, 4)

let 'a' represent the angle between AB and AC

cos a = (Vector AB * Vector AC)/( |AB| |AC|)

cos a = (4*2 + 1*4)/(((4^2 + 1^2)^0.5) * ((2^2 + 4^2)^0.5))

cos a = 12/(17^0.5 * 20^0.5)

cos a = 0.650791374

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a = arccos 0.650791374

a = 49.4 degrees

the angle between AB¯¯¯¯¯ and AC¯¯¯¯¯ is 49.4 degrees.