Thread: Angle A when three lenghts are known

Hi,

Can anybody tell me the formula for getting an angle A when I have the lengths of the 3 sides of a triangle. Ive forgotten how to do it.

Thanks for the help

To find an angle when you have the lengths of the three sides you can use the following formula:

a^2 = b^2 + c^2 - 2(bc)cosA

where a is the length of the side opposite A, and b and c are the lengths of the other sides.

Math Guru

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bye

Hi prof

How to post the images like this in the messages


thanx

Originally Posted by vms

Hi prof

How to post the images like this in the messages


thanx

the prof created the image and then uploaded it. If you have an image you want to display you can simply attach it when you create the post