document.write( "Question 138394: what is the answer to 2y(cubed)-18y(squared)+28y=0 \n" ); document.write( "
Algebra.Com's Answer #101069 by solver91311(24713)\"\" \"About 
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Your question is more correctly put: \"What are the answers to...\" Since you have a cubic, or 3rd degree polynomial equation, the Fundamental Theorem of Algebra tells us there must be three roots.\r
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\n" ); document.write( "\n" ); document.write( "In general terms, a cubic equation is a rather tiresome thing to have to solve. Fortunately, however, your equation has a pair of common factors in every term:\r
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\n" ); document.write( "\n" ); document.write( "\"2y%5E3-18y%5E2%2B28y=0\"\r
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\n" ); document.write( "\n" ); document.write( "You can factor out a \"2\" and a \"y\" from every term:\r
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\n" ); document.write( "\n" ); document.write( "\"2y%28y%5E2-9y%2B14%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "You can divide both sides by 2 to get:\r
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\n" ); document.write( "\n" ); document.write( "\"y%28y%5E2-9y%2B14%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "Now, the Zero Product Rule tells us that either \"y=0\" or \"y%5E2-9y%2B14=0\"\r
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\n" ); document.write( "\n" ); document.write( "But notice that \"y%5E2-9y%2B14=0\" is just a quadratic equation, and an easily factorable one at that. \r
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\n" ); document.write( "\n" ); document.write( "So, 0 is one of the elements of your solution set, and the roots of the quadratic are the other two.
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