I have two decision variables, $SL_i$ = the amount I'm contributing to my student loan debt in month i, and $fiftySL_i$ = 1 if I contribute at least \$50 over the minimum payment (so contribute $350) in month i.
I've set up the truth table below, and want to eliminate the second and third scenarios. I've only used truth tables for strictly binary variables, so I'm not sure how to do this.
\begin{array}{|c|c|} \hline SL_i& fiftySL_i \\ \hline < 350& 0 \\ \hline < 350& 1\\ \hline \ge 350& 0 \\ \hline \ge 350& 1\end{array}
$$\begin{align} & 350 \cdot \delta \le x \le 349.99 + \delta\cdot (U-349.99)\\ &\delta \in \{0,1\}\\ & 0 \le x \le U \end{align} $$