Question 1149564
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the longest line segment that can be drawn in a right rectangular prism that is 14 cm long, 11 cm wide and 8 cm tall


is 3D diagonal from one corner/vertex "at the floor" to the opposite corner/vertex "at the ceiling".


Its length is, applying the Pythagorean theorem in 3D is


    L = {{{sqrt(14^2+11^2+8^2)}}} = {{{sqrt(381)}}} = 19.519 centimeters.


It is the <U>longest diagonal</U>" in this 3D box (= prism).
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