Finding the lengths of the sides using a given angle

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Homework Help Overview

The discussion revolves around a problem involving a triangle where one angle is given as 51.168821565 degrees. Participants are exploring how to find the lengths of the sides using the law of sines, while also considering the implications of having only one angle provided.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the implications of having only one angle and whether it is sufficient to determine the side lengths of a triangle. There are attempts to apply the law of sines and considerations of theorems regarding triangle properties, such as the sum of angles and the relationship between sides and angles.

Discussion Status

The discussion is ongoing, with some participants noting that an infinite number of triangles can be formed with just one angle, while others emphasize the need for additional information, such as another angle or a side length, to apply the law of sines effectively. A participant has clarified that one side is given, which may lead to further exploration of the problem.

Contextual Notes

There is a mention of a second angle being 90 degrees, which alters the problem's context, and a side length of 25 is introduced, suggesting that the problem may be moving towards a more defined scenario.

greggory
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Homework Statement


Well, here is the problem. Assuming that the shape is a triangle, find the lengths of all sides, given one angle is 51.168821565 degrees using the law of sine.

sin(51.168821565) = 0.785398161...

The Attempt at a Solution


I basically tried using the theorems, such as that all angles will add up to 180 degrees and A+B > C always.

I tried to find the lengths, but couldn't. Help would be appreciated.

EDIT:

I tried this:
d = opposite
h = hypotnues
sin 51.168821565 = d / h
d / h = 0.785398161

Does this mean there are infinite numbers that can fit side lengths?
 
Last edited:
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There are infinitely many triangles with only one angle given.
 
Last edited:
greggory said:

Homework Statement


Well, here is the problem. Assuming that the shape is a triangle, find the lengths of all sides, given one angle is 51.168821565 degrees using the law of sine.
This is impossible. As th4450 said, there are an infinite number of different triangles having that angle. Draw the angle choose any point on one ray, any point on the other and connect them.n Go back and reread the problem. You have to be given at least one side.

sin(51.168821565) = 0.785398161...


The Attempt at a Solution


I basically tried using the theorems, such as that all angles will add up to 180 degrees and A+B > C always.

I tried to find the lengths, but couldn't. Help would be appreciated.

EDIT:

I tried this:
d = opposite
h = hypotnues
sin 51.168821565 = d / h
d / h = 0.785398161

Does this mean there are infinite numbers that can fit side lengths?
That formula works only for right triangles. You say that you are to use the "law of sine". Do you know what that is? (Not the definition of sine.) In order to use the "law of sine" to find the length of a side, you must already know two angles and one side.
 
Well, I accidently left out some information. The other angle is 90 degrees, which means that the other angle must be 38.831178435, right? Also, one given side is 25(if I read the problem right this time).
 

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