Answer:
7 units
Step-by-step explanation:
You want the distance between A(-4, -5) and D(3, -5).
The given coordinates are the end points of a horizontal line segment. Its length is the difference of the x-coordinates:
length = 3 -(-4) = 3+4 = 7
The length of the rectangle is 7 units.
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Additional comment
The width of the rectangle is AB = 3 -(-5) = 8 units. This is the difference of the y-coordinates of the vertical line segment end points.