<PRE><B>Question 126670</B>
I&#39;ll do one of these, and then you can do the rest:


{{{10x^2+21x-10=0}}}


Use the quadratic formula:



{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
{{{x = (-21 +- sqrt( 21^2-4*(10)*(-10) ))/(2*10) }}} 
{{{x = (-21 +- sqrt(441+400))/(20) }}}
{{{x = (-21 +- sqrt(881))/(20) }}}


881 is prime, so this is reduced to lowest terms.  The solution set consists of the following two elements:

{{{x[1] = (-21 + sqrt(881))/(20) }}}
{{{x[2] = (-21 - sqrt(881))/(20) }}}
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