Question 1156377
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{{{S=ut+(1/2)gt^2}}}

{{{2S=2ut+gt^2}}}

{{{gt^2+2ut-2S=0}}}

{{{t=(-2u+- sqrt(4u^2-4g(-2S)))/(2g)}}}


{{{t=(-2u+- 2*sqrt(u^2+2gS))/(2g)}}}


{{{t=(-u+- sqrt(u^2+2gS))/g}}}