Question

Solve for angle A, B & C
a=55
b=25
c=72

Answer 1

law o' cosines for this one

Answer 2

I did it, i got my answer, totally makes sense, teacher said its wrong. Looked it up online, says my answer is right.

Answer 3

then tell your teacher he/she made a mistake

Answer 4

But if you do it with law of cosines, you get something that makes no sense.

Answer 5

A=39.3, B=x, C=123

Answer 6

So 123+39.3=?? idk, but then you get B=17.7
But, law of cosines says its 16.7

Answer 7

this is what wolfram gets, see if it matches your answer
http://www.wolframalpha.com/input/?i=triangle+a%3D55+b%3D25+c%3D72

Answer 8

123.9, 39.35, 16.75

Answer 9

o.O Well she said my Angle A and C were right?

Answer 10

rounding error is my guess

Answer 11

you only should use law of cosines once, get the largest angle, then use law of sines for the next largest, then subtract total from 180 to get smallest angle

Answer 12

http://i.imgur.com/CfpiZ.png

Answer 13

theta=60, so..