Let:
x = Number of sodas purchased
y = Number of hamburgers purchased
The food truck charges $3 for sodas, so the total cost for sodas will be:
3*x=3x
also, it charges $8 for each hamburger, hence, the total cost for hamburgers will be:
8*y = 8y
Since Jack wants to spend no more than $30, the total cost must be less or equal than $30:
[tex]\begin{gathered} \text{Total cost }\leq\text{ 30} \\ \text{Total cost = total cost for sodas+total cost for hamburgers} \\ 3x+8y\le30 \end{gathered}[/tex]
