# Which is the area of a circle with a diameter of 7 units?

Nov 14, 2015

The area of the circle is $\frac{49 \pi}{4}$
The area $A$ of a circle with radius $r$ is given by $A = \pi {r}^{2}$
So, a circle with diameter $7$ has radius $\frac{7}{2}$ and thus area
$\pi {\left(\frac{7}{2}\right)}^{2} = \frac{49 \pi}{4}$