solve for td=(1/2) at^2
\(\frac{1}{2}at^2=d\ \ \ \ |multiply\ both\ sides\ by\ 2\\\\at^2=2d\ \ \ \ |divide\ both\ sides\ by\ a\\\\t^2=\frac{2d}{a}\ \ \ \ |square\ root\ both\ sides\\\\t=\sqrt\frac{2d}{a}\)
\(d=\frac{1}{2}at^2\\ 2d=at^2\\ t^2=\frac{2d}{a}\\ t=\sqrt{\frac{2d}{a}}\)
