1. Note 8: Applications
A surveying team are trying to find the height of a hill. They take a ‘sight’ on the top of the hill and find that the angle of elevation is 23º. They move a distance of 250 metres on level ground directly away from the hill and take a second ‘sight’. From this point, the angle of elevation is 19º. Find the height of the hill, correct to the nearest metre.

2. B = 180º – 23º = 157º C = 180º – 157º – 19º = 4º h = 1400.34 x sin19ºm
157
B = 180º – 23º = 157º
C = 180º – 157º – 19º = 4º
h = x sin19º
= m
The hill is 456 metres high
AC = m

3. Page 420
Exercise 13I