I assume you made your drawing. If so, it should be clear
RQ: use law of cosines
bearing is 90-z, such that
tan(z) = (240cos50°)/(240sin50°+120)
for the bird, draw a side-view diagram -- it will make things easier.
Come back if you get stuck, and show what you have so far.
Three points P, Q and R are on level ground. Q is 240 m from P on bearing of 230°. R is 120 m to the east of P.
A) Using a scale of 1 cm to represent 40 m, draw a diagram to show the positions of P,Q and R in the space provided below.
B) Determine
(i) The distance R from Q
(i) The bearing of R form Q
C) A vertical post stands at P and another one at Q. A bird takes 18 seconds to fly directly from the top of the post at Q to the pot of the post at P. Given that the angle of depression of the top of the post at P from the top of post at Q is 9°.
Calculate:
i) The distance to the nearest meter, the bird covers;
ii) The speed of the bird in km/h
1 answer