Answer: 4100 ft^2
Step-by-step explanation: To solve, you need to split the figure into 2 rectangles like this: (see attached image.) . To find the width of the smaller rectangle, subtract 50 from 70. 70-50=20. The width is 20 ft. Now we can use the area formula to solve. A=l*w. A=(30)(20). A=600 ft^2. Now solve for the larger rectangle. To find the length of it, add 30 and 40. 30+40=70. Now find the area A=(70)(50). 3500 ft^2. Add both area answers together. 600+3500=4100 ft^2