Day 5: We are Coming to an end with The Cosine Rule

We were back to Mr. Pandza's class to learn more challenging equations to solve triangles that did not have a right angle.

What to do when the triangle is not a right angle??

It's actually very easy! Basically all you need to do is label your triangle correctly, memorize the formula, and then plug in all the information (solve)! It's really as simple as that!

First, you must label your triangle correctly! Each angle gets a letter (A, B, or C). To label the sides of a triangle, label it the lower case letter of the opposite angle (a, b, or c). Now you are ready to take these rules into ACTION!

THE COSINE RULE

The Cosine rule is usually applied to triangles in which we do not know a pairing of an angle and the opposite side.

The Equations:

The cosine rule can be remembered because it looks very similar to the Pythagora's Theorem with a little extra pizazz!

EXAMPLE!

Use the Law of Cosines to solve:

For being such a great three students Mr. Pandza ordered us pizza after our final lesson! It was a great way to end this section!

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