Let the selling price for walnuts be x and the selling price for the almonds be y.
On the first day, Erick sold 2 pounds of walnuts and 4 pounds of almonds for $28. This implies that
[tex]\begin{gathered} 2x\text{ + 4y =28 } \\ \text{equation 1} \\ \end{gathered}[/tex]On the second day, 4 pounds of walnuts and 3 pounds of almonds for $31.
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