I think I have it right, but I don’t exactly understand what I’m supposed to do. I need someone to break it down and explain to me.

Answer:
The expressions that show how she determined the cost of her sandwich is;
[tex]\begin{gathered} s+2.56=9.82 \\ \text{where} \\ s=\text{ \$}7.26 \end{gathered}[/tex]Explanation:
Given that Aliyah had a sandwich and a salad and her total bill for lunch was $9.82.
This means that the sum of the cost of the sandwich and the cost of the salad is $9.82.
Given that the salad cost $2.56.
Let s represent the cost of the sandwich;
[tex]s+2.56=9.82[/tex]solving for s let us subtract 2.56 from both sides;
[tex]\begin{gathered} s+2.56-2.56=9.82-2.56 \\ s=7.26 \\ s=\text{ \$}7.26 \end{gathered}[/tex]Therefore, the expressions that show how she determined the cost of her sandwich is;
[tex]\begin{gathered} s+2.56=9.82 \\ \text{where} \\ s=\text{ \$}7.26 \end{gathered}[/tex]