SINE AND COSINE RULES – PRACTICE QUESTIONS 1. Use sine rule to find x to 1 decimal place. x 13.9 cm 49° 62° 2. Use sine rule to find y to 1 decimal place. 58° y 51° 7.2 m 3. Use sine rule to find z to 2 significant figures. z 11 cm 31° 65° 4. Use cosine rule to find a to the nearest centimetre. 21° 12.3 cm 16.1 cm a 5. Use cosine rule to find b to 3 significant figures. b 9.9 m 48° 17.1 m 6. Use cosine rule to find c to 2 decimal places. 16.6 m c 63° 25.5 m 7. Use sine rule to find d to 2 significant figures. d 16.1 cm 41° 24.5 cm 8. Use sine rule to find e to the nearest degree. 8.4 cm 7 cm e 57° 9. Use sine rule to find f to 2 significant figures. 64° 8.1 cm f 14.5 cm 10. Use cosine rule to find g to 2 significant figures. 56 cm 70 cm g 91 cm 11. Use cosine rule to find h to 2 significant figures. 11.1 m 18.9 m h 10.8 m 12. Find x to 3 significant figures. 9.8 m x 70° 43° 13. Find y to 1 decimal place. 65° 8.2 cm 7.6 cm y 14. Find z to 1 decimal place. z 16 cm 46° 17 cm 15. Find x to 3 significant figures. 13.8 cm 15.4 cm x 40° 16. Find y to 1 decimal place. 8.1 m 14.7 m y 15.3 m 17. Find z to 2 significant figures. 41° 560 m 470 m z 18. Find x to 3 significant figures. 36 cm x 44° 51° 19. Find y to 3 significant figures. y 98 cm 209 cm 247 cm 20. Find z to 2 significant figures. 75 cm 47° 68 cm z 21. Find the area of the triangle. Give your answer to 3 significant figures. 61° 15 cm 12 cm 22. Find the area of the triangle. Give your answer to the nearest square centimetre. 16.6 cm 50° 19.7 cm 23. ABC is a triangle. The area of ABC is 96 cm2. Find the size of angle BAC to the nearest unit. A 17.8 cm B 19.3 cm C 24. DEF is a triangle, with an area of 225 cm2. Find the size of angle DFE. Give your answer to 2 significant figures. D 26.2 cm F 38.5 cm E 25. Find the area of triangle GHI. Give your answer to the nearest square centimetre. G 4.5 cm 33° 3.2 cm 76° I H I 26. JKL and KML are triangles. Find the size of the angle KML. Give your answer to 2 significant figures. M K 50° 32.1 m 10.7 m 69° J 19° L 27. NOP and OQP are triangles. Find the size of QP, to 3 significant figures. Q O 58° 61° 21.8 cm 38° N P 29.7 cm 28. Find the area of the triangle. Give your answer to the nearest square centimetre. 9.0 cm 13.5 cm 14.4 cm