Final answer:
The correct expression showing the Lopez family's remaining money after x days is 2000 - 150x, which accounts for spending $150 each day from their initial $2000.
Step-by-step explanation:
The Lopez family started with $2000 and spent $150 each day. To calculate the remaining money after x days, we need to subtract the product of $150 and the number of days (x) from the initial amount. The correct expression representing the amount of money they had left after x days is 2000 - 150x. Therefore, if they spent money for x days, we calculate the leftover amount by multiplying $150 by x, and then subtracting that total from $2000. This type of expression is common in budgeting or financial planning, where you have an initial budget and daily expenditures. The expression helps track the remaining funds over time.