$\"\"$

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(a)

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The polar equation is $\"\"$ , where $\"\"$ is in miles.

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Evaluate the function for several values of $\"\"$ in its domain and use this points to graph the function.

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(1) Draw the coordinate plane.

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(2) Graph the function $\"\"$ .

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Graph :

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$\"\"$

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$\"\"$

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(b)

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The polar equation is $\"\"$ .

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Multiply each side by $\"\"$ .

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$\"\"$

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To find the rectangular form of this equation replace $\"\"$ with $\"\"$ and $\"\"$ with $\"\"$ .

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Since $\"\"$ , the equation can be written as $\"\"$ .

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$\"\"$

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$\"\"$

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An equation in rectangular form to model the seismic waves is $\"\"$ .

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$\"\"$

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(c)

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The epicenter is the center of the circle formed by $\"\"$ or $\"\"$ .

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The general form of circle is $\"\"$ has a diameter of $\"\"$ .

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Compare the polar form with the general form

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The diameter is $\"\"$ .

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Hence the radius of the circle is $\"\"$ .

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Therefore, people within a $\"\"$ miles radius of the epicenter felt the effects of the earthquake.

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$\"\"$

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(a)

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Graph :

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$\"\"$

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(b) An equation in rectangular form to model the seismic waves is $\"\"$ .

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(c) People within a $\"\"$ miles radius of the epicenter felt the effects of the earthquake.