MediumLaws of sines & cosines

OpenStax, Algebra and Trigonometry 2e §10.2 Non-right Triangles: Law of Cosines · Exercise 18 · Trigonometry · Laws of sines & cosines

Non-right Triangles: Law of Cosines · Exercise 18

Use the Law of Cosines to solve for the missing angle of the oblique triangle. Round to the nearest tenth.

$a = 16, b = 31, c = 20;$ find angle $B .$

Its source prints no answer for this problem, so there's nothing to check against.

~8 minWritten answer · compare with the solution

OpenStax, Algebra and Trigonometry 2e · §10.2 Non-right Triangles: Law of Cosines · Exercise 18

Stuck? A gentle nudge

No hints for this one.

Something off?

Workspace

Your working

Check your full solution

Upload photos of your handwritten work or a PDF, and Lemma will read it and tell you whether it's right — and where it first goes wrong if not.