Upload
johnny-hern
View
217
Download
0
Embed Size (px)
Citation preview
1
Circle Formulae 2
The area of a circle
Tandi Clausen-May
Click the mouse
2
Click the mouse only when you see
or
If you click too soon you will miss the best bits.
Click the mouse Click to see
Click the mouse
3
The area
of a circle
Tandi Clausen-May Click the mouse
4Click the mouse
We saw in Circle Formulae 1 that…
Circumference= × Diameter
Now, what about the area?
5
Imagine a circle made out of strands of beads.
Open it out.
Click the mouseClick to see the circle open
6
circumference
radius (half the diameter)
Let’s watch that again.
It’s a triangle!
base = circumference
Click to see the circle open again
height = radius (half the diameter)
Click the mouse
7
circumference
radius (half the diameter)
= Circumference × Radius 2
Area of the triangle circle
Area of the triangle
We know how to find the area of a triangle.
Click the mouse
= Base × Height 2
8
= Circumference × Radius 2
Area
Summary
Click the mouse
9
The End
Tandi Clausen-May