Length of a missing side no angle given :(

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SUMMARY

The discussion centers on the impossibility of determining the length of a fourth side in an irregular plot given only the lengths of three sides. Participants agree that additional information, such as angles or area, is necessary to calculate the missing side accurately. The cosine rule is suggested as a potential method for deriving a formula, but without sufficient data, the exact length remains indeterminate. The consensus is that the fourth side's length can vary widely based on the configuration of the plot.

PREREQUISITES
  • Understanding of the cosine rule in geometry
  • Familiarity with irregular polygons
  • Basic knowledge of triangle properties
  • Concept of side lengths and their relationships
NEXT STEPS
  • Study the cosine rule and its applications in triangle calculations
  • Research methods for calculating areas of irregular polygons
  • Explore geometric properties of triangles and their implications
  • Learn about the relationship between side lengths and angles in polygons
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Mathematicians, geometry students, architects, and anyone involved in land surveying or irregular plot analysis will benefit from this discussion.

t3rom
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I'm given an irregular shaped plot with 3 sides, and have been asked to find the fourth missing side, no other detail is given. Is it possible to find the missing side? If so, then how? Here is what it looks like roughly:

8wids2.jpg
 
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I don't think that it's possible. What if it looks like this?
polygon.jpg
 
Looks like you need one more piece of data ... angles, area - etc... however you could write a formula for ? based on the missing info.
 
Borg said:
I don't think that it's possible. What if it looks like this?
View attachment 79370

That can be a possibility as it's a plot with irregular sides.

Windadct said:
Looks like you need one more piece of data ... angles, area - etc... however you could write a formula for ? based on the missing info.

Can I write a formula without the missing data? If so then how, please elaborate..
 
t3rom said:
That can be a possibility as it's a plot with irregular sides.
Can I write a formula without the missing data? If so then how, please elaborate..

Draw a diagonal and apply the cosine rule.
 
t3rom said:
I'm given an irregular shaped plot with 3 sides, and have been asked to find the fourth missing side, no other detail is given. Is it possible to find the missing side? If so, then how? Here is what it looks like roughly:

8wids2.jpg
It's not possible to find the fourth side, assuming that all we know is the lengths of the three sides. The fourth side could be anywhere from 0 to (a triangle) to 29.9 + 19.5 + 30.05 (in which you get a straight line.
 

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