math
posted by lindsay on .
Dave walked from point A to point B due North East for a distance of 20m. He immediately changed direction and walked 50m from B to C on a bearing of 110 degrees.
i. Calculate the distance AC
ii. Find the bearing of C from A

1. d = 20m[45o] + 50m[110o]
X = 20*cos45 + 50*cos110 = 2.96 m.
Y = 20*sin45 + 50*sin110 = 61.1 m.
tanAr = Y/X = 61.1/2.96 = 20.64189
Ar = 87.23o = Reference angle.
A = 87.23 + 180 = 92.8o
d = Y/sinA = 61.1/sin92.8 = 61.2 m.= AC.
2. Bearing = 92.890 = 2.8o West of North.