Question 882137
{{{x=(-9+- sqrt(81-4*(-5)3))/(-10)}}}
{{{x=(-9+- sqrt(81+60))/(-10)}}}
{{{x=(-9+- sqrt(141))/-10}}}
{{{x=(9+- sqrt(141))/10}}},  141=3*47
{{{x=(9+- 11.874)/10}}}


Examining your four choices and comparing to your expression for x, you must have exactly one positive solution and one negative solution.  Your added form is positive and your subtraction form is negative.  You can eliminate choice 3.  The added form is estimable to be about (10+10)/10=2, approximately.  This suggests choice number neither choice 1 nor 2.
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The subtraction form?  approx. -2/10=-1/5.  This looks like choice 4 is the closest choice.  <b>{-0.29, 2.09}</b>. 


Finish computing x.  <b>{-0.2874, 2.0874}</b>.