Question

Help with checking work on law of cosines

Answer 1

Use the Law of Cosines to solve each triangle with the given measures. Round answers to the nearest tenths. a = 0.48 yd, b = 0.63 yd, c = 0.75 yd

Answer 2

Which angle would you like to solve for first using the law of cosines?

Answer 3

\[C=\cos^{-1}\frac{ .48^2+.63^2-.75^2 }{ 2(.48)(.63) }\]

Answer 4

C first :p

Answer 5

sorry one moment alot to type in my calculator lol

Answer 6

Ok.
Let me check.
\(C = \cos ^{-1} \dfrac{a^2 + b^2 - c^2}{2ab} \)

Answer 7

Good. It looks like you have it correct.

Answer 8

Did you get C = 83.8 deg?

Answer 9

Still working on my parenthesis
I keep getting it mixed up S:

Answer 10

83.85 yes

Answer 11

C=83.85 B=56.63

Answer 12

Remember, they want the nearest tenth.

Answer 13

I round it at the end

Answer 14

oh wait this is the ennd

Answer 15

loool so C=83.9 B=56.6

Answer 16

Correct.
Now for A, you can use the law of cosines again, or use the shortcut
A = 180 - B - C

Answer 17

180-83.9-56.6

Answer 18

39.5

Answer 19

Correct. Good job!

Answer 20

Woop

Answer 21

Its nice how in these types you can just simply move around digits and you can immediately get B

Answer 22

Thank you for your help :D