How to Find the Center of a Circle
Draw a circle., Sketch a chord between two points., Draw a second chord., Make another line between A and C. This third chord (AC) should stretch through the center of the circle – but you will need to draw one more line to find the exact center...
Step-by-Step Guide
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Step 1: Draw a circle.
Use a compass, or trace any circular object.
The size of the circle does not matter.
If you're finding the center of an existing circle, then you don't need to draw a new circle.
A geometry compass is a tool specifically designed to draw and measure circles.
Buy one in a school or office supply store! -
Step 2: Sketch a chord between two points.
A chord is a straight line segment that links any two points along the edge of a curve.Name the chord AB.
Consider using a pencil to sketch your lines.
This way, you can erase the marks once you've found the center.
Draw with a light touch so that it'll be easier to erase. , This line should be parallel and equal in length to the first chord that you drew.
Name this new chord CD.,,, If you have drawn straight and accurate lines, then the center of the circle lies at the intersection of the crossed lines AC and BD.Mark the center point with a pen or pencil.
If you only want the center point marked, then erase the four chords that you drew. -
Step 3: Draw a second chord.
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Step 4: Make another line between A and C. This third chord (AC) should stretch through the center of the circle – but you will need to draw one more line to find the exact center point.
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Step 5: Join B and D. Draw one final chord (BD) across the circle between Point B and Point D. This new line should cross over the third chord (AC) that you drew.
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Step 6: Find the center.
Detailed Guide
Use a compass, or trace any circular object.
The size of the circle does not matter.
If you're finding the center of an existing circle, then you don't need to draw a new circle.
A geometry compass is a tool specifically designed to draw and measure circles.
Buy one in a school or office supply store!
A chord is a straight line segment that links any two points along the edge of a curve.Name the chord AB.
Consider using a pencil to sketch your lines.
This way, you can erase the marks once you've found the center.
Draw with a light touch so that it'll be easier to erase. , This line should be parallel and equal in length to the first chord that you drew.
Name this new chord CD.,,, If you have drawn straight and accurate lines, then the center of the circle lies at the intersection of the crossed lines AC and BD.Mark the center point with a pen or pencil.
If you only want the center point marked, then erase the four chords that you drew.
About the Author
Martha Reyes
Experienced content creator specializing in DIY projects guides and tutorials.
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