Can someone help explain how to use law of cosines?

Question

amistre64 · Answer

plug in numbers into the formula and work it ...

darkbluechocobo · Answer

Well when I say explain I mean like changing around the formula

amistre64 · Answer

chagne it to what?

amistre64 · Answer

theres addition, and some multiplication

spose you had:

c = a + b + abk

use algebra and change it around as needed

darkbluechocobo · Answer

Well I was confused when switching it around how to work around the sqrt, but yeh what you said would solve it

amistre64 · Answer

you got something more concrete we can work with?  or do you got this handled :)

darkbluechocobo · Answer

Well one of my example problems would be: Use the Law of Cosines to find the specified missing value. Approximate your answer to the nearest tenth. If C = 60°, a = 120 in, b = 66 in, find c. This would kinda settle how i feel bout working around with it

darkbluechocobo · Answer

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amistre64 · Answer

c^2 = a^2 + b^2 + 2ab cos(C)

yeah, thats pretty much plug and play with the information

amistre64 · Answer

notice when C = 90, this is just the pythag thrm :)

darkbluechocobo · Answer

so $$c^2=14400+4356+2(120)(66)\cos(60)?$$