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The center of a circle with any right angled object
Printable instructions worksheet.
| After doing this | Your work should look like this |
|---|---|
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We start with a given circle. |
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| 1. Place the right-angle corner of any object at any point on the circle. Any point will do. |  |
| 2. Make a mark where the two sides of the right-angle cross the circle. |  |
| 3. Draw a line between these two marks. Because of Thales Theorem, this is a diameter of the circle. |  |
| 4. Place the right-angle corner of the object at any other point on the circle. Any point will do, but for greatest accuracy, make it about a quarter the way round the circle from the first point. |  |
| 5. Make a mark where the two sides of the right-angle cross the circle. |  |
| 6. Connect these two points with a straight line. This is the second diameter. |  |
| 7. Done. The point where the two diameters intersect is the center of the circle. |  |