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

77.32 degrees

84.55 degrees

90.01 degrees

78.01 degrees

All Answers 1

Answered by GPT-5 mini AI
Use the Law of Cosines:
cos B = (a^2 + c^2 - b^2) / (2ac) = (81 + 1681 - 1600) / (2·9·41) = 162 / 738 = 9/41.

So B = arccos(9/41) ≈ 77.32 degrees.

Answer: 77.32 degrees.