The height of an interior residential door is about 7 ft.
Doors on commercial buildings or upscale residences may be taller. The usual width is about 3 ft.
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My front door measures 6 2/3 ft high by about 3 ft wide. My bedroom doors are 2 1/2 ft wide. The minimum for ADA-compliant doors is 2 2/3 ft.
V=L X W X H
1,296=6 x w x 24
1,296=144 x w
1296/144=w
9=width
-2 < -3 (I think so anyway)
The slope for points (-9, 5) (-17, 5) is m = 0
