A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

A triangle has side lengths of 9 in, 13 in, and 20 in. What is the measurement of this triangle’s largest angle? 29.9° 50.1° 129.9° 136.2°

  • This Question is Closed
  1. wolf1728
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    When we know all 3 sides, we use the Law of Cosines: The largest side is 20 so C is the largest angle cos(C) = (a^2 + b^2 -c^2) / (2*a*b) cos (C) = (9^2 + 13^2 -20^2)/ =2*9*13 cos (C) = (81 + 169 -400) / 234 cos (C) = -150 / 234 cos (C) = -0.641025641 The arc cosine of -0.641025641 is 129.87 Degrees

    1 Attachment
  2. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    that is correct

  3. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.