# Circle

Keywords: circle, perimeter, area

**Perimeter**

$$P=2r\pi =d\pi $$

**Area**

$$A={r}^{2}\pi =\frac{{d}^{2}\pi}{4}$$

Keywords: circle, perimeter, area

**Perimeter**

$$P=2r\pi =d\pi $$

**Area**

$$A={r}^{2}\pi =\frac{{d}^{2}\pi}{4}$$