document.write( "Question 1177833: A landscape architect is planning a circular flower
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Algebra.Com's Answer #853723 by ikleyn(53560) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " The solution by @mananth is incorrect due to arithmetic errors on the way.\r
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document.write( "pi*(r+25)^2 - pi*r^2 = (1/2)*pi*r^2\r\n" );
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document.write( "Cancel pi in both sides\r\n" );
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document.write( "(r+25)^2 - r^2 = (1/2)*r^2\r\n" );
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document.write( "r^2 + 50r + 625 - r^2 = (1/2)*r^2\r\n" );
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document.write( "50r + 625 = (1/2)r^2\r\n" );
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document.write( "r^2 - 100r - 1250 = 0\r\n" );
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document.write( "Use the quadratic formula and find  r = .\r\n" );
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document.write( "It gives a unique meaningful positive solution x =  = 111 cm, rounded.    ANSWER\r\n" );
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