Answer
$$R= \frac{J Q}{I^2 t } .$$
Work Step by Step
To solve the given equation for $R$, we multiply both sides by $J$ and then divide both sides by $I^2 t$ as follows:
$$ Q=\frac{I^2 t R}{J}\Longrightarrow J Q=I^2 t R\Longrightarrow \frac{J Q}{I^2 t }=\frac{I^2 t R}{I^2 t }\\ \Longrightarrow R= \frac{J Q}{I^2 t } .$$
