MathVillage

Step 1: Cut circle into 1/8's

Step 2: Cut circle into wedges

Step 3: Rearrange the wedges to form a parallelogram.

Step 4: Notice the dimensions of this parallelogram.

Step 5: Radius is "r" and half the circumference is π•r.

Step 6: The area of a parallelogram is length x width.

Area of a circle = π• r • r