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**In this module, you can study ****how to use trig ratios (sine, cosine and tangent) to find an unknown side length in a right triangle.**

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A right triangle can have its right angle at the top.

**Study and practice**

- Study using trig ratios to find the length of a sideThis page from mathsisfun.com explains how to choose which trig ratio (sine, cosine or tangent) to use when you need to find the length of a side. There is also a set of interactive practice problems at the bottom of the page.
- Quiz yourself on finding an unknown side length using trigDo you know how to find an unknown side length using sine, cosine and tangent? Check your understanding with this online quiz at mathopolis.com

Use these search terms to find your own resources:

*solving right triangles with trigonometrysolving right triangles with sines, cosines and tangents*