20.2 Trigonometric ratios (SOHCAHTOA) — Practise

Work independently. Estimate where useful, show your method, and check units. In the mixed questions, choose the method and give a reason.

1. A right triangle has angle 30° and hypotenuse 14 cm. Find the opposite side.
2. A right triangle has angle 60° and hypotenuse 10 cm. Find the adjacent side.
3. A right triangle has angle 45° and adjacent side 8 cm. Find the opposite side to 3 significant figures.
4. The opposite and adjacent sides are 5 cm and 12 cm. Find the angle to 1 decimal place.
5. The hypotenuse is 13 cm and one leg is 5 cm. Find the angle opposite that leg.
6. A right triangle has angle 30° and adjacent side 6 cm. Find the hypotenuse.
7. Find the opposite side when the hypotenuse is 20 cm and angle is 30°.
8. A right triangle has opposite 9 cm and adjacent 12 cm. Find the hypotenuse.