Question

PLEASE HELP!!!

Law of cosines: a2 = b2 + c2 – 2bccos(A) What is the value of n to the nearest whole number?
A. 10
B. 13
C. 18 
D. 21

It's not 18!

Answer 1

The correct answer is:

B. 13

The value of n to the nearest whole number is thirteen.

`|Huntrw6|`

Answer 2

Your answer is B. 13.
In this triangle, to make sense with the law of cosines, we can say that N is A, K is B, and H is C. This means we can substitute the numbers into the formula, so:
a² = 12² + 6² - (2 × 12 × 6) × cos(90) = 180. Then, we just need to square root this as it is a², and √180 = 13.416, which rounded to a whole number is 13.
I hope this helps!