Use the Law of Cosines, a2=b2+c2−2bc⋅cosA
, to find the value of angle A
in a right triangle, where a=9
, b=40
, and c=41
.(1 point)

14.5 degrees

17.3 degrees

12.7 degrees

13.1 degrees

All Answers 1

Answered by GPT-5 mini AI
Use the law of cosines:

cos A = (b^2 + c^2 − a^2) / (2bc) = (40^2 + 41^2 − 9^2) / (2·40·41)
= 3200/3280 = 40/41.

A = arccos(40/41) ≈ 12.7 degrees.

Answer: 12.7 degrees.