(1) A circle with an area of 8π square centimeters is dilated so that its image has an area of 32π square centimeters. What is the scale factor of the dilation?A 2B 4C 8D 16
Q. (1) A circle with an area of 8π square centimeters is dilated so that its image has an area of 32π square centimeters. What is the scale factor of the dilation?A 2B 4C 8D 16
Given Information: Original area of the circle is 8π square centimeters. New area of the circle is 32π square centimeters. The area of a circle is proportional to the square of its radius.
Define Scale Factor: Let's call the scale factor 'k'. The new area is k2 times the original area because when a figure is dilated, the area is multiplied by the square of the scale factor.
Set Up Equation: Set up the equation: k2×original area=new area. So, k2×8π=32π.
Solve for k2: Divide both sides by 8π to solve for k2: k2=8π32π.
Final Scale Factor: Simplify the equation: k2=4.
Final Scale Factor: Simplify the equation: k2=4. Take the square root of both sides to solve for k: k=2 or k=−2. Since a scale factor cannot be negative, k=2.
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