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How Do You Find a Missing Side of a Right Triangle Using Cosine? Instructional VideoHow Do You Find a Missing Side of a Right Triangle Using Cosine? Instructional Video
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Instructional Video

How Do You Find a Missing Side of a Right Triangle Using Cosine?

Curated and Reviewed by Lesson Planet

Trigonometry? What's trigonometry. Well, something to do with triangles, right? Right! Right triangles! In this problem, find the missing length of one of the sides. So set this up as a ratio: cosine(A) = adjacent side length divided by the length of the hypotenuse. Still not sure what to do? Then watch this video as the instructor walks through the steps.

20 Views 5 Downloads
Concepts

legs, cosine, trigonometric ratios, hypotenuse, length, measurement, opposite, inverse, ratios, right triangles, triangles, sides, sine, tangent

Additional Tags

right triangle, sine, cosine, tangent, sides, legs, length, hypotenuse, adjacent, opposite, ratio, Trigonometry, math
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Resource Details

Grade
6th - 11th
Subjects
Math
2 more...
Resource Type
Instructional Videos
Media Length
5:07
Audience
For Teacher Use
Instructional Strategy
Flipped Classroom
Usage Permissions
Fine Print

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