Question:

Need help with algebra 2 triangle prob plz!!!?

by  |  earlier

0 LIKES UnLike

okay dudes or dudettes,

Solve the triangle ABC:

A=120 degrees, B = 40 degrees, c=35

I knew how to do this but I forgot. Can someone show me how to do it, or at least gimme the formula so I can figure it out? thanks!

 Tags:

   Report

10 ANSWERS


  1. sinA/a=sinB/b=sinC/c

    A+B+C=180

    first solve for angle C using the second one. turns out to be

    120+40+C=180

    C=20

    sin(20)/35=sin(120)/a

    .00977a=.866

    a=88.623

    sin(20)/35=sin(40)/b

    .00977b=.643

    b=65.779

    make it a good day


  2. Really hate math

    But i dont even study :D

  3. there are 180 degrees in a triangle.  therefore, 180-120-40=your third angle.  this is true for all triangles. so, C = 20

    to find your other two sides, you have to use the law of sines and cosines.



    Law of sines says (sinA/a) = (sin B/b) = (sinC/c)

    so, use the equation: sin20/35 = sin 120/a

    solve for a.

  4. You have to apply just 2 theorems for triangle:

    A + B + C = 180 degrees

    a/sinA = b/sinB = c/sinC

  5. what exactly r  u trying to find? u got all 3 angle measures....

  6. You have two angles, so 180 - (120 + 40) = 20 degrees for angle C

    Using the sine rule to solve for side a, you have

    35/ sin 20 = a/ sin 120

    a = 35 * sin 120 / sin 20

    a = 88.62

    You can use either the sine rule or cosine rule to find side b, but for simplicity's sake we'll use the sine rule using the set C.

    35/ sin 20 = b/sin 40

    b = 35 * sin 40 / sin 20

    b = 65.78

    therefore

    A = 120 degrees

    B = 40 degrees

    C = 20 degrees

    a = 88.62

    b = 65.78

    c = 35


  7. C = 180° - A - B

    a = cSinA/SinC

    b = cSinB/SinC

  8. looks like you have to use the sin, cos & tan formulas

    (remember soh cah toa?)

  9. use law of sines and cosines.

  10. I need the whole equation to solve this

Question Stats

Latest activity: earlier.
This question has 10 answers.

BECOME A GUIDE

Share your knowledge and help people by answering questions.