Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

gonzo
Lv 6
gonzo asked in Science & MathematicsMathematics · 1 decade ago

how do you figure out the angles of a triangle knowing the sides?

i need to find the angles of a right triangle. the base on its side is 12 with a height of one. i don't need the length of the hypotenuse, i need to figure out what the other angles are. which equation can give me the answer

7 Answers

Relevance
  • 1 decade ago
    Favorite Answer

    Acute angles of right triangles can be found based on ratios of the appropriate sides. the ratio of the opposite leg, (the height in your example) to the base is named the tangent, (abreviated tan), of the angle in question. The ratio 1/12 expressed as a decimal is .08333... Once you know the tangent of the angle the simplest way to find the angle is to use any scientific calculator. You will note these canculators have a key for sin (sine) cos (cosine), other ratios and tan. This is the one we need. Since we know the tan and not the angle we will need to fine the inverse tan of .08333.

    To find the inverse of the tangent you will need to press an inverse button before you press tan. That will vary on different calculators and can be: arc, inv or 2nd. Now put in the decimal .08333. Press enter and you should have your answer in degrees. Your answer is 4.76 in degrees. (.0831 in radians, another ratio.)

    Some calculators need to be put into degree mode, before you do the problem, if that is the format you want. Also some calculators require that the decimal be entered before the inverse tangent is taken. Experiment with your calculator. After a short while you should be rewarded with the correct answer.

    The other acute angle is the complement of 4.76 degrees or 85.23. Incidently its tangent is 12/1 or 12. The inverse tangent of which is 85.23 degrees.

    Good luck.

    Peter

    Source(s): I am a retired math teacher. Your problem is a common question for trigonometry students.
  • 1 decade ago

    Base of right triangle given as 12 and height given as 1. smallest angle will be tan-1(1/12) = 4.7636 deg. The larger angle will be 90 - 4.7636 = 85.2364 deg.

  • kermit
    Lv 4
    4 years ago

    if it incredibly is a staggering perspective triangle, then between the angles is ninety, and in accordance to the priority, yet another perspective is 37 we could desire to recognize the 0.33 perspective.. properly, reality: the sum of all 3 angles in a triangle is one hundred eighty (each and each time. and no count what triangle it incredibly is) consequently, the 0.33 perspective plus the different 2 upload as much as one hundred eighty (perspective) + ninety + 37 = one hundred eighty perspective = one hundred eighty - ninety - 37 perspective = fifty 3 to discover the aspects, first % any of the angles (aside from the ninety) shall we are saying we chosen 37.. the guideline says that sin(37) = (the area opposite to the perspective)/hypotenuse shall we are saying that the scale of the area opposite to the hypotenuse is x then sin(37) = x/25.5 x = (25.5)sin(37) you're able to do an identical element for the relax area by utilising the perspective we got here across above (fifty 3) yet shall we use an identical perspective yet a distinctive technique, yet another rule says: cos(37) = area adjoining to the perspective/hypotenuse permit the area adjoining to the perspective be y cos(37) = y/hypotenuse y = (25.5)cos(37) reliable success!!

  • Anonymous
    1 decade ago

    If the triangle is ABC with the right angle at B, AB = 12, BC = 1, then:

    tan(A) = 1/12

    tan(C) = 12

    You should find that A + C = 90deg.

  • 1 decade ago

    A trick that I use is

    SOH, CAH, TOA

    Sine= Opposite/ Hypotnuse

    Cosine= Adjacent / Hypotnuse

    Tangent= Opposite/Adjacent

    So if you draw your triangle and lable all your sides and angles you can fill in two of the pieces in order to find the missing piece.

  • Anonymous
    1 decade ago

    There are few trigonometric formulas from which u can easily solve such type of problems.

    for a triangle ABC-

    sinA=height/hypo

    cosA=base/hypo

    tanA=height/base

    so for your prob.if AB=12,BC=1then

    tanA=1/12

    A=inverse of tan(1/12)

    A=4.76

    A+C=90(as it is a rt triangle)

    C=85.2

  • 1 decade ago

    Check back in a few hours ... I'll ask my kids

Still have questions? Get your answers by asking now.