We have to find the value of cosine for an angle with point ( 5, - 12 ) on its terminating side. First we have to find the hypotenuse ( Adjacent = 5, Opposite = 12 ) : c^2 = 5^2 + 12^2 = 25 + 144 = 169; c = sqrt(169 ), c = 13. Cosine for an angle = Adjacent / Hypotenuse = 5 / 13 = 0.385. Answer: The value of cosine is 5/13 or 0.385.