Answer:
342 ft squared
Explanation:
You know how to find the area of a rectangle: Multiply the dimensions together (length x width).
You can also see that the garden is inside the deck, and that it is also a rectangle. Therefore, you can find the area of the deck ONLY by subtracting the area of the small rectangle from the big one.
First, find the area of the big rectangle:
18 * 25 = 450 ft squared
Now, find the area of the small one:
9 * 12 = 108 ft squared
Finally, subtract the area of the small rectangle from the area of the big one:
450 - 108 = 342 ft squared
Hope this helps! Please comment on this answer if you have any questions :)