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Author Topic: I need math help
Starsnuffer
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Find measure of vertex angle in iso. triangle with sides 22 22 and 28

I don't know how to do it.

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King of Men
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42.

No, seriously. It comes to 79 degrees.

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Starsnuffer
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please explain how
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Dagonee
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Hint: Draw a line from the vertex perpendicular to the baseline. You now have two right triangles to work with and the lengths of the sides of those triangles.

That should be a plenty big enough hint.

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Starsnuffer
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Wow, I feel like a retard, ive been working on this for like 15 minues plus.
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Airguitarist
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You could also use the Law of Cosines:

A^2=B^2+C^2-2*B*C*cos(alpha)

Where A, B and C are the lengths of the sides of the triangle, and alpha is the angle oposite side A. Since you want to find the vertex, you would use A=28, B=22 and C=22, then use the inverse cosine function to solve for the angle.

(edit): wow, you guys are fast.

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Dagonee
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Starsnuffer, once you calculate it, please post what you got for whichever trig ratio you used and the final angle. Now I'm curious, but I don't want to do the math. [Smile]
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