Finding Length of Lines in Picture

In summary, the pentagon cannot be formed because the distances between the perimeter points are 1cm.
  • #1
Natasha1
493
9
Could someone help me find the length in cm of the lines between the points in the picture attached.

The 3 angles around point 6 are 120 degrees each. This is also the case for point 8 which is linked to point 2, 3 and 7.

Now the 3 angles formed by the lines leaving point 7 are also 120 degrees.

If the distance between point 1 and 2, 2 and 3, 3 and 4, 4 and 5 is 1 cm.

What is the total distance of the lines?
 

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  • #2
Natasha1 said:
The 3 angles around point 6 at 120 degrees each. This is also the case for point 8 which is linked to point 2, 3 and 7.

Now the 3 angles formed by the lines leaving point 7 are also 120 degrees.

Well they can't all be at 120 degrees, or else they would be on top of each other.

Can you post the exact problem statement, as well as your attempted solution? Thanks.
 
  • #3
Tom Mattson said:
Well they can't all be at 120 degrees, or else they would be on top of each other.

Can you post the exact problem statement, as well as your attempted solution? Thanks.

I can't get an answer that's the reason of my post. I made the question up. Are you sure they would be on one and each other :-(((.

I'm pretty sure you are not correct, I could have 3 points with 3 angles formed around each of them with angles of 120 degrees.
 
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  • #4
Natasha1 said:
I can't get an answer that's the reason of my post.

I'm not asking for the answer, I'm asking for your attempted solution. Our site policy (which you agreed to before posting) requires that you show some work before receiving help.

I'm pretty sure you are not correct, I could have 3 points there of degree 3 with angles of 120 degrees.

OK, I see what you're saying. When I see "120 degree angle" I think "120 degree angle measured counterclockwise from the positive x axis". That would put your rays at 120, 240, and 360 degrees. But even so, your angles don't look like they are in those positions.
 
  • #5
The distances of the lines between points 5,6,4 and 2,8,3 (which are 2 isoceles triangles) is 2 cm.

This is how much I get as I have 4 sin 30 = 2

I am missing the distances from points 1,7 and 6,7 and also 7,8 to get my total distance can someone help :-) please
 
  • #6
Natasha? you made this question up?...an attempt at drawing the problem yields (at least for me) a contradiction.

All five perimeter points are 1cm away from each other and therefore they must surely form a regular pentagon. By drawing rays with the specified 120 deg angles you can see where it becomes impossible to continue.

http://img109.imageshack.us/img109/1306/pentagon0bu.gif
 
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What is the importance of finding the length of lines in a picture?

Finding the length of lines in a picture is important for various reasons. It can help with scale and proportion, as well as determining the perspective of the image. It is also useful in measuring distances and angles, which can provide valuable information for analyzing and understanding the image.

What tools are commonly used to find the length of lines in a picture?

There are several tools that can be used to find the length of lines in a picture. These include rulers, protractors, and measuring tapes. More advanced techniques involve using software programs or mathematical formulas to calculate the length of lines.

How do you accurately measure the length of curved lines in a picture?

Measuring curved lines can be more challenging than straight lines, but there are methods that can be used to accurately measure them. One technique is to break the curved line into smaller straight segments and measure each segment individually. Another method is to use a flexible ruler or string to trace the curvature of the line and then measure the length of the ruler or string.

What are some common errors to avoid when finding the length of lines in a picture?

When finding the length of lines in a picture, it is important to avoid certain errors that can affect the accuracy of the measurement. These include not using a consistent unit of measurement, not measuring from the same starting point, and not holding the measuring tool or picture steady. It is also important to ensure that the measuring tool is aligned correctly with the line being measured.

Can the length of lines in a picture be used to determine the dimensions of objects?

Yes, the length of lines in a picture can be used to determine the dimensions of objects. By measuring the length of a known line and using the scale or ratio of the image, the length of other lines can be converted into real-world measurements. This can be useful in fields such as architecture and engineering, where precise measurements are necessary for designing and constructing structures.

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