Let L be the amount of gas Angela has at distance d. At d=0 she has 26, and we know that every 48 miles the gas decreases 2 gallons, so the rate of decrease of gas per mile is
[tex]\frac{2\text{ }}{48}=\frac{1}{24}[/tex]
Then, the linear equation that models this problem is
[tex]L=-\frac{1}{24}d+26[/tex]
(I used the minus sign since the amount decreases).
The gas will run out of gas whe she has driven
[tex]\begin{gathered} 0=-\frac{1}{24}d+26 \\ \frac{1}{24}d=26 \\ d=624\text{ miles} \end{gathered}[/tex]
Then the graph that best fits the model is number Z. And the answer is D.