Q. find the arc length of a sector if the radius is 5cm and the area of the sector is 74.5
Understand Relationship: Understand the relationship between the area of a sector and the arc length. The area of a sector A of a circle with radius r and central angle θ in radians is given by the formula A=21×r2×θ. To find the arc length L, we use the formula L=r×θ. We need to find θ first to calculate L.
Calculate Central Angle: Calculate the central angle (θ) using the area of the sector.We have the area of the sector (A=74.5cm2) and the radius (r=5cm). We can rearrange the area formula to solve for θ:A=(1/2)⋅r2⋅θ74.5=(1/2)⋅52⋅θ74.5=(1/2)⋅25⋅θ74.5=12.5⋅θθ=74.5/12.5θ=5.96 radians (approximately)
Calculate Arc Length: Calculate the arc length L using the central angle θ and the radius r. Now that we have θ, we can use the arc length formula: L=r×θL=5cm×5.96radiansL=29.8cm
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