Question 358502
Your way? Do you have a different quadratic formula??

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{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
{{{x = (-14 +- sqrt( 14^2-4*5*(-3) ))/(2*5) }}}
{{{x = (-14 +- sqrt( 196+60 ))/(10) }}}
{{{x = (-14 +- sqrt( 256 ))/(10) }}}
{{{x = (-14 +- 16)/(10) }}}
Take it from there and solve for the two solutions.