For a certain logo

MATHEMATICS · Subjective · CBSE · Mathematics · Areas Related to Circles · Areas Related to Circles

Problem

For a certain logo, a sector of a circle has an arc length of 22 cm and an area of 154 cm2154\,\text{cm}^2. The sector’s centre and boundaries form a single continuous piece of metal. (a) Form an equation involving the radius rr and central angle θ\theta (in degrees) using the information about arc length. (b) Form a second equation involving rr and θ\theta using the information about the area of the sector. (c) Solve the simultaneous equations obtained in parts (a) and (b) to find the exact values of rr and θ\theta. (d) Using the values of rr and θ\theta, determine the perimeter of the metal piece (include the two straight sides and the curved edge).

Related theory

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