Trigonometry / Pythagoras A 1. ABCD is a rhombus whose diagonals are 24 cm and 40 cm. Calculate the perimeter of this rhombus. B D 40 cm C 24 cm 2. A telegraph pole is connected to the ground by wires. Each wire is 8 metres long and is fixed to the ground 4.5 metres from the pole. h 8m Use this information to calculate the height of the telegraph pole. 4.5 m 3. The diagram opposite shows a ramp outside a building. The side view of the ramp is a right angled triangle. 32 cm 0 Calculate, a , the angle made by the ramp with the ground. a0 1.66 m 4. Michael is looking at a hot air balloon in the sky. From Michael’s position the angle of elevation to the balloon is 350. Calculate h, the height the balloon is above the ground. h 350 GROUND 75 m 2.7 km 5. Two runners leave from the same starting point and head off in different directions. Using the information in the diagram opposite, Calculate how far apart the runners are. 42 0 3.5 km 60 m 6. Three trees are positioned as shown opposite. A 75 0 38 0 Calculate the distance between trees A and C. C 7. A flagpole 7 metres high is connected to the ground by a metal wire. If the bottom of the wire is 4.2 metres from the flagpole, calculate the length of the wire. 7m 4.2 m 8. The side view of the roof of a house is in the shape of an isosceles triangle, as shown. Calculate the length r of the sloping side of the roof. 5m r 14 m d 9. The diagram shows the end view of a symmetrical water trough. 50 0 40 cm Calculate the distance d. 60 cm B 10. A golfer is standing 120 metres from a hole. He hits the bal,l which travels a distance of 132 metres, and ends up 14 metres from the hole. Calculate, x0, the angle by which the golfer was off target. 120 m x0 14 9.5mm 132 m 11. The diagram opposite shows the side view of a shed, in the shape of a rectangle and a right angled triangle. 3.3 m Calculate the width of the shed. 3.6 m 2.1 m width 12. An aeroplane takes off at an angle of 180, as shown below. 850 m h 180 Calculate the height, h, the aeroplane is above the ground after it has travelled 850 metres. 13. A flagpole 5 metres high is supported by a metal wire which is connected to the ground, 3.2 metres from the flagpole. Calculate the size of the angle the wire makes with the ground. 5m 3.2 m B 14. The diagram oppsite shows triangle ABC with measurements as shown. Show that cos x = 15 . Do not use a calculator. 5 cm A x 7 cm 6 cm C P 5 cm 15. The diagram opposite shows a triangle PQR. Given that cos 600 = 12 , find the length of PR. Q 60 0 Do not use a calculator. 8 cm R E 117 0 16. Calculate the area of the triangle 11.8 cm 14 cm F G 17. The diagram shows the position of an airport and two aeroplanes flying at the same height.. Calculate the distance between the aeroplanes. 2200 m 3000 m 15 0 18. A piece of metal in the shape of a triangle has measurements as shown. (a) By calculating the largest angle in the triangle, determine if the triangle is right angled. (b) Calculate the area of metal in the triangle 7 cm 13 cm 15 cm N 19. In the diagram opposite AB represents a main road 28 kilometres long running due north. AC and CB represent secondary roads. Calculate the size of angle BAC. B 23 km 28 km 65 0 C A 20. The diagram shows a triangular shaped garden. A jogger runs from one corner of the garden to another, as shown.. 1000 Calculate how far he has run. 50 0 65 m A 21. A rhombus ABCD has diagonals of length AC = 14 cm and BD = 22 cm. D Calculate the size of angle x. B 14 cm x C 22 cm 22. The diagram opposite shows a tower with a weather vane on top. From a point A, the angle of elevation to the top of the weather vane is 510. From B, the angle of elevation to the top of the weather vane is 670. The distance from A to B is 25 metres. h Calculate the height, h, that the top of the weather vane is from the ground. A 23. Two identical industrial chimneys are 40 metres apart. From a point A, the angle of elevation to the top of one chimney is 700 and from the same point the angle of elevation to the top of the other is 600. B 25m 40 m h Calculate the height, h, of the chimneys. 700 600 A