Question 166183
{{{v = (12 +- sqrt(12^2 - 4(24)))/2}}}
{{{v = (12 +- sqrt(144-96))/2}}}
{{{v = (12 +- sqrt(48))/2}}}
{{{v = (12 +- 4*sqrt(3))/2}}}
You missed a division by 2 in front of the square root.
{{{v = 6 +- highlight(2)*sqrt(3)}}}