Question 363193
{{{f(t)=-30t^2+120t+0 }}}
Find t when, 
{{{-30t^2+120t+0=60}}}
{{{30t^2-120t+60=0}}}
{{{t^2-4t+2=0}}}
{{{(t^2-4t+4)+2=4}}}
{{{(t-2)^2=2}}}
{{{t-2=0 +- sqrt(2)}}}
{{{highlight(t=2 +- sqrt(2))}}}