From the proportion we can easily find the final sector area formula: Sector Area = α × πr² / 2π = α × r² / 2 The same method may be used to find arc length - all you need to

Step 3: Substitute the values and calculate the area of a sector of a circle. Area = 3.1415 × (12) 2 × (45° / 360) Area = 3.1415 × 144 × (45° / 360) Area = 3240 cm 2. So, the sector area of a circle