Q20 of 68 Page 15

Figure 15.18 shows a sector of a circle of radius r cm containing an angle θ°. The area of the sector is A cm2 and perimeter of the sector is 50cm.

(i)(ii)



Given,


Radius of the sector = r cm


Angle subtend = θ


Area of sector = A cm2


Perimeter of sector = 50cm


Area of sector =


Perimeter of sector =






(i)



First equation


Second equation


Put value of from equation first to equation second



Area = 25r-r2


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