PreCalculus
posted by Gabby .
Point B is 12 km north of point A. Point C is 9 km from point B on a bearing of 060°. Find the distance from A to C.

Looks like the angle at B is 150° and we can just use the cosine law:
AC^2 = 12^2 + 9^2  2(12)(9)cos 150°
= 225  216( √3/2)
= ....
AC = + √ .....
I got AC = appr 20.3