**CHAPTER 5: Trigonometry (1) The Sine Rule**

**Exercise 5c Questions and Solutions**

**Number 6:**

An aeroplane flies from a town X on a bearing off N45⁰E to another town Y, a distance of 200km. It then changes course and flies to another town Z on a bearing of S60⁰E. If Z is directly east of Z, calculate, correct to 3 significant figures,

a) the distance from X to Z

b) the distance from Y to XZ (WAEC)

**Number 7:**

A mass hangs from a horizontal beam by two strings as shown in the figure below.

Use the data in the figure to calculate the length of the longer string.

**Number 8:**

An aircraft is timetabled to travel from A to B. Due to bad weather it floes from A to C then from C to B, where AC and CB make angles of 27⁰ and 66⁰ respectively with AB. If |AC| = 220km, calculate |AB|

Number 9: Two wires support an electricity pole as shown in the figure below

If the wires make angles 58⁰ and 67⁰ with the ground and |AB| = 21m, calculate the lengths of the wires.

**Number 10:**

From points A and B on level ground, the angels of elevation of the top of a building are 25⁰ and 37⁰ respectively. If |AB| = 57m, calculate, to the nearest metre, the distances of the top of the building from A and B if they are both on the same side of the building.

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