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Q:

# How do you measure diameter?

A:

If the radius of the circle is known, the diameter formula is diameter=2R, where R equals the circle's radius. If the circumference of the circle is known, the diameter is found using diameter=C/Pi, where C is the circumference and pi is approximately 3.142.

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If the area of a circle is known, the diameter is the square root of 4A/Pi, where A is the area of the circle and Pi is approximately 3.142. The diameter of the circle is the length of the line through the center of the circle that touches two of the points on its edge The center of the circle is the midpoint of the diameter. A diameter may also be referred to as a chord, which is any line that joins two points on a circle. The diameter is the longest chord on any circle.

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## Related Questions

• A:

The most direct way of measuring the radius of a circle is to measure from the center of the circle to the outside border. If you cannot determine the center of the circle, measure the circumference of the circle and divide that number by 2?.

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• A:

The domain of a circle is the X coordinate of the center of the circle plus and minus the radius of the circle. The range of a circle is the Y coordinate of the center of the circle plus and minus the radius of the circle. It is easy to remember which coordinates domain and range refer to because X is alphabetically before Y, and domain is alphabetically before range.

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• A:

To find the circumference of a circle, multiply the diameter by pi or double the radius times pi. Pi is an unchanging number that rounds off to 3.14.