Question 114347

{{{5x^2+5x+1= 0}}}

{{{x[1,2]=(-b +- sqrt (b^2 -4*a*c )) / (2*a)}}}

{{{x[1,2]=(-5 +- sqrt (5^2 -4*5*1 )) / (2*5)}}}

{{{x[1,2]=(-5 +- sqrt (25 - 20 )) / 10}}}

{{{x[1,2]=(-5 +- sqrt (5 )) / 10}}}

{{{x[1,2]=(-5 +- 2.24) / 10}}}


{{{x[1]=(-5 + 2.24) / 10}}}
	
{{{x[1]=- 2.76 / 10}}}

{{{x[1]= - 0.276 }}}


{{{x[1,2]=(-5 - 2.24) / 10}}}

{{{x[1,2]=( - 7.24) / 10}}}

{{{x[1,2]=( - 0.724) }}}


Check:

{{{5x^2+5x+1= 0}}}…..plug in {{{x}}}

{{{5(- 0.276 )^2+5(- 0.276 )+1= 0}}}

{{{5(0.076176)+5(- 0.276 )+1= 0}}}

{{{0.38 - 1.38 + 1= 0}}}

{{{1.38 - 1.38 = 0}}}

{{{0 = 0}}}
	
{{{5x^2+5x+1= 0}}}…..plug in {{{x}}}


{{{5(- 0.724)^2+5(- 0.724)+1= 0}}}


{{{5(0.524) - 3.62+1= 0}}}

{{{2.62- 3.62 + 1= 0}}}

{{{3.62- 3.62 = 0}}}

{{{0 = 0}}}