Question 515087
{{{ y^4 +45 = 14y }}}
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{{{ y^4 -14y + 45 = 0 }}}
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factor
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{{{ (y^2 -9)(y^2 -5) = 0 }}}
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keep factoring
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{{{ (y-3)(y+3)(y+sqrt(5))(y-sqrt(5)) = 0 }}}
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So the roots are 
{{{ y=3 }}}
{{{ y=-3 }}}
{{{ y=-sqrt(5) }}}
{{{ y=sqrt(5) }}}
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Done.