Question 367075
If {{{2x+5}}} is a factor, then
{{{2x=-5}}}
{{{x=-5/2}}} is a zero.
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{{{graph(300,300,-4,2,-3,3,0,2x^3-3x^2-12x+20)}}}
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It looks promising.
For complete verification, plug {{{x=-5/2}}} into the equation and verify that the output is equal to zero.