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Recall some of the terms related to a circle: Determine the radius of the circle whose diameteris given in units. radius = units Circumference: If the circumference of a circle is 12π units, determine the diameter. C = πd ? Diameter: units Area formula If the area of a circle is 9π ft2, determine the radius. A = πr2 ? feet Radius: r = feet The circumference of the circle shown is 10π feet.Answer the questions related to the circle. Area ≈ feet2 Diameter: feet Radius: feet Circumference = ft Find the radius of a circle if the area = 64π ft2. Then find the exact circumference of the circle. Write your answer in terms of π. Radius = ft π A = πr2 C = 2πr A sector of a circle with an 12 inch radius and central angle measure of 60º is shown. Find the area of the sector. Leave your answer in terms of π. (Don't use 3.14 for π). Sector Area = π in2 A = π( )2 A = πr2 360 ? m 360 60 ? 24 ? 12 ? A circle is shown with a radius of 21 inches. Find the length of the arc formed by a 240º angle. Write your answer in terms of π. (Don't use 3.14 for π). Arc Length = π in L = 2πr L = 2π( ) 240 ? 360 ? m 360 28 ? 21 ? A circle is shown with a radius of 12 units.Find the length of arc PQ formed by a 135º angle.Use 3.14 for π. Arc Length ≈ in L = 2πr m 360 A sector of a circle with an 10 m radius and central angle measure of 45º is shown. Find the area of the sector. Use 3.14 for π. A = πr2 Sector Area ≈ m2 m 360 |