We have to calculate the area of each rectangle using the formula:

where A is the area, b the base, and h the height.
• Jamal's garden: b = 5 and h = 4

• Emily's garden: b = 4 and h = 7

• Kylie's garden: b = 4 and h = 5

Finally, we add all the areas to get the area of all gardens :

Answer: 68ft²