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 154cm2. The sector’s centre and boundaries form a single continuous piece of metal.
(a) Form an equation involving the radius r and central angle θ (in degrees) using the information about arc length.
(b) Form a second equation involving r and θ 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 r and θ.
(d) Using the values of r and θ, determine the perimeter of the metal piece (include the two straight sides and the curved edge).