Final answer:
To describe the event planner's budget, we can write the inequality 18x + 19y ≤ 820.
Step-by-step explanation:
In this situation, we can use the given information to write an inequality that describes the event planner's budget. The cost of each garland is $18 and the cost of each centerpiece is $19. Let's assume the planner ordered 'x' garlands and 'y' centerpieces. The total cost of the garlands would be 18x and the total cost of the centerpieces would be 19y. According to the given budget, the total cost should be no more than $820. Therefore, the inequality in standard form would be:
18x + 19y ≤ 820