Answer :
Given the expression:
[tex]d=r\cdot t[/tex]to solve for r, we have to move its factor to the other side doing the opposite operation. In this case we have that t is multiplying r, so the t is going to pass to the other side dividing d, so we get the following:
[tex]\begin{gathered} d=r\cdot t \\ \Rightarrow r=\frac{d}{t} \end{gathered}[/tex]therefore, the equation to solve for r is r=d/t