[SOLVED]Law of Cosines - Solve This Triangle

Law of cosines problem:

"Use the Law of Cosines to solve the triangle."

...............C

............./..|

.........../....|

5.4 yd /......|4.2 yd

......../.......|

......./.......|

.....A------B

......2.1 yd

So,

M<A=

M<B=

M<C=

a=4.2 yd

b=5.4 yd

c=2.1 yd

I never wind up with the correct angle degrees. In the back of my book, it seems like the answers are always off of what I have calculated. Does anyone know how this might have happened?

For M<A, I got 45.41 degrees. Hopefully that is the right answer.

Thanks for any help in advance.

-Alex

Re: Law of Cosines - Solve This Triangle

I made calculations for angle A by using the cosine formula that is Cos A = (b^2+c^2-a^2)/2bc and the value I got is 45.38 degrees. Little variation in such questions should be acceptable for approximations / rounding off.

Re: Law of Cosines - Solve This Triangle

Quote:

Originally Posted by

**ibdutt** I made calculations for angle A by using the cosine formula that is Cos A = (b^2+c^2-a^2)/2bc and the value I got is 45.38 degrees. Little variation in such questions should be acceptable for approximations / rounding off.

thanks.