document.write( "Question 947550: the area of a circle is increased by 45 pi square centimetres if the diameter is increased by 6 cm. what was the original circumference of the circle? \n" ); document.write( "

Algebra.Com's Answer #578195 by josgarithmetic(39617) $\"\"$ $\"About$

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Original circumference, $\"2%28pi%29r\"$ .\r
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\n" ); document.write( "\n" ); document.write( "Increased radius, $\"r%2B6%2F2\"$ ;\r
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\n" ); document.write( "\n" ); document.write( "Increaese of area, $\"pi%2A%28r%2B6%2F2%29%5E2-pi%2Ar%5E2=45%2Api\"$
\n" ); document.write( " $\"%28r%2B3%29%5E2-r%5E2=45\"$
\n" ); document.write( " $\"r%5E2%2B6r%2B9-r%5E2=45\"$
\n" ); document.write( " $\"6r-9=45\"$
\n" ); document.write( " $\"6r=45%2B9\"$
\n" ); document.write( " $\"6r=54\"$
\n" ); document.write( " $\"highlight%28r=9%29\"$ , the original radius.\r
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\n" ); document.write( "\n" ); document.write( "The original circumference was $\"2%28pi%29%2A9\"$ or $\"highlight%2818%28pi%29%29\"$ . \n" ); document.write( "

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