What is the difference between –7 and 3?

The difference is 10.
-7+x=3
x=10

A) (2+6) x (6+3) = 72 in^2
b) width: 6 + 2 = 8
    length: 6 + 3 = 9

Because the green part is a square, so the width is just 6 in plus 2 in.
Now, we also know the height of the blue rectangle, 8 in.
The area of the blue rectangle is 24in^2 --> 24/8 = 3. The width of the blue rectangle is 3in.
3 + 6 is the length of the entire figure