document.write( "Question 707869: Solve the polynomial equation 125x^3+216=0
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Algebra.Com's Answer #435896 by jim_thompson5910(35256) $\"\"$ $\"About$

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125x^3+216 = 0\r
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\n" ); document.write( "\n" ); document.write( "(5x)^3 + 6^3 = 0\r
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\n" ); document.write( "\n" ); document.write( "(5x + 6)((5x)^2 - 5x*6 + 6^2) = 0 ... use the sum of cubes formula\r
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\n" ); document.write( "\n" ); document.write( "(5x + 6)(25x^2 - 30x + 36) = 0\r
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\n" ); document.write( "\n" ); document.write( "5x + 6 = 0 or 25x^2 - 30x + 36 = 0\r
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\n" ); document.write( "\n" ); document.write( "5x = -6 or 25x^2 - 30x + 36 = 0\r
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\n" ); document.write( "\n" ); document.write( "x = -6/5 or 25x^2 - 30x + 36 = 0\r
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\n" ); document.write( "\n" ); document.write( "So one solution is x = -6/5\r
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\n" ); document.write( "\n" ); document.write( "The other two solutions can be found by solving 25x^2 - 30x + 36 = 0\r
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\n" ); document.write( "\n" ); document.write( "You solve 25x^2 - 30x + 36 = 0 for x by using the quadratic formula. \n" ); document.write( "

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