  # Identify Trigonometric Ratios in Right-Angled Triangles

In this worksheet, students will work out the given trigonometric ratio in right-angled triangles. Key stage:  KS 3

Curriculum topic:   Geometry and Measures

Curriculum subtopic:   Solve Right-Angled Triangle Problems

Popular topics:   Angles worksheets, Geometry worksheets

Difficulty level:   #### Worksheet Overview

In a right-angled triangle, the sides and the angles are connected by three trigonometric ratios. The three trig ratios are:   A quick way to remember this is to memorise the word

SOHCAHTOA

Example

Use the side lengths of this triangle to state the value of cosθº Label the sides adjacent, opposite and hypotenuse in relation to the angle θº. SOHCAHTOA

The side adjacent to the angle θ has length 3.

The hypotenuse has length 5.

The correct trig ratio is COS so cos θº= 3 ÷ 5

If you need a reminder of all these formulae, you can check back to this page by clicking on the red button on the right of the screen.

Let's try some questions now.

### What is EdPlace?

We're your National Curriculum aligned online education content provider helping each child succeed in English, maths and science from year 1 to GCSE. With an EdPlace account you’ll be able to track and measure progress, helping each child achieve their best. We build confidence and attainment by personalising each child’s learning at a level that suits them.

Get started 