Area of a circle is defined by [tex] \pi r^2[/tex]. We can test this by inserting some values of the radius and seeing if they equal the area.
1
pi*(1)^2
=1pi or pi
2
pi*(2)^2
=pi*4 or 4pi
3
pi*(3)^2
=pi*9 or 9pi
As we can see, this formula satisfies the given areas, so it is correct.
:)
