the ship has been lost at sea, the Canadian coast guard has sent three vessels to set up a perimeter around the spot of the lost ship's last communication. The distance between ship A and B is 40 km, the distance between ship B and c is 54 KM. The angle at the ship is 42 degrees. The distance between ship A nad C ,to the nearest km is
By the cosine law:
AC^2 = 40^2 + 54^2 - 2(40)(54)cos42°
= .....