Answer:
80 ft.
Step-by-step explanation:
When finding the total area of two rectangles, you must find the area of each rectangle, then add the products.
6 x 7 = 56
8 x 3 = 24
56 + 24 = 80
Adding the unit: 80 ft.
6 = -2b (cancel -2b on both sides)
6/-2 = b (divide both sides by -2)
-3 = b (simplify 6/2 to 3)
now switch sides
Answer: b = -3