Circle Formulae 2

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Circle Formulae 2
The area of a circle Tandi Clausen-May
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2
Click the mouse only when you see
or If you click too soon you will miss the best
bits.
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Click to see
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3
The area
of a circle
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Tandi Clausen-May
4
We saw in Circle Formulae 1 that
Circumference
? Diameter
Now, what about the area?
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5
Imagine a circle made out of strands of
beads. Open it out.
Click to see the circle open
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6
Lets watch that again.
Click to see the circle open again
circumference
Its a triangle!
base circumference
height radius (half the diameter)
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7
We know how to find the area of a triangle.
radius (half the diameter)
circumference
Area of the triangle
Base Height 2
Circumference Radius 2
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8
Summary
Circumference Radius 2
Area
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9
The End
Tandi Clausen-May