What is the longest line segment that can be drawn in a right rectangular prism that is 12 cm​ long, 11 cm​ wide, and 8 cm​ tall?

1 answer

To find the longest line segment that can be drawn in a right rectangular prism (also called a box), we need to calculate the length of the space diagonal of the prism. The formula to find the length of the space diagonal \( d \) of a rectangular prism with dimensions \( l \) (length), \( w \) (width), and \( h \) (height) is:

\[ d = \sqrt{l^2 + w^2 + h^2} \]

In this case, the dimensions are:

  • Length \( l = 12 , \text{cm} \)
  • Width \( w = 11 , \text{cm} \)
  • Height \( h = 8 , \text{cm} \)

Plugging in the dimensions into the formula:

\[ d = \sqrt{(12)^2 + (11)^2 + (8)^2} \]

Calculating each term:

\[ (12)^2 = 144 \] \[ (11)^2 = 121 \] \[ (8)^2 = 64 \]

Now, add these values together:

\[ 144 + 121 + 64 = 329 \]

Now, take the square root:

\[ d = \sqrt{329} \]

Calculating the square root:

\[ d \approx 18.14 , \text{cm} \]

Therefore, the longest line segment that can be drawn in the right rectangular prism is approximately 18.14 cm.