Length of a missing side no angle given :(

  • Thread starter Thread starter t3rom
  • Start date Start date
  • Tags Tags
    Angle Length
Click For Summary
Finding the fourth side of an irregular plot with only three known sides is not possible without additional information, such as angles or area. The discussion emphasizes that the fourth side could vary widely, depending on the configuration of the existing sides. Suggestions include using the cosine rule if more data were available, but without it, no definitive formula can be established. The consensus is that additional details are essential to determine the missing side accurately. Therefore, the problem remains unsolvable with the given information.
t3rom
Messages
54
Reaction score
0
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
 
Mathematics news on Phys.org
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.
 

Thread 'Trigonometry problem of interest'

Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
View full post »

Similar threads

B Understanding the Pythagorean Theorem
Replies
38
Views
4K
MHB Finding the Leg Lengths of a Right Triangle with an Acute Angle of 22°
Replies
2
Views
1K
Unit Circle Double Angle Derivations
Replies
6
Views
344
MHB Calculating Triangle Side Length with Known Angles and Radius
Replies
2
Views
1K
MHB Find the height and base of a trapezium
Replies
1
Views
2K
A How Does Non-Euclidean Geometry Differ from Euclid's Postulates?
Replies
3
Views
2K
MHB Why Can't a Right Triangle Have Sides that Add Up to the Area of Squares?
Replies
2
Views
2K
MHB Find cos(x) and sin(x) if angle x has these properties....
Replies
1
Views
2K
MHB Find the volume of the hexagonal-shaped plastic box
Replies
4
Views
1K
MHB Triangle ABC has area 25*sqrt(3). if Angle BAC=30 degrees, find |AC|=|BC|=?
Replies
1
Views
2K