Using dimensional analysis, which one of the following equations is dimensionally correct?

$)=>\frac{m}{s^2},v=>\frac{m}{s},x=>(m),t=>((s)$

$x=\frac{v}{t}$

$t^2=\frac{x}{a}$

$x^2=2av$

$v=2ax$

$x=at$