( 1)

S=nπR？ /360

Where r represents the radius of the sector and n represents the central angle of the sector.

(2)

S= 1/2*LR

Where l represents the arc length of the sector and r represents the radius of the sector.

Sector arc length formula

L=nπR/ 180

R represents the radius of the sector and n represents the central angle of the sector.