Volume question?

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3 Answers
Feb 21, 2018

12cm

Explanation:

This is a generalisation of Pythagoras' theorem to 3 dimensions.

The length of the diagonal is:

62+52+92=36+25+81=142144=12

Feb 21, 2018

The answer is 12 cm.

Explanation:

Firstly, you draw a diagonal line through the base of the rectangular prism. Now you get two triangles and can find the hypotenuse. 62+52=612

Now you can make a triangle and imagine that the diagonal line going through the whole prism is the hypotenuse and calculate it with the given height.

612+92=1422

If you take the root out of 142 and turn it into decimal, you get 11.916...

Feb 22, 2018

12cm

Explanation:

Similar to the Pythagoras Theorem, the length of the diagonal for a rectangular prism is: l2+w2+h2

Therefore, d=62+52+92

d=36+25+81

d=142

d11.92

12cm is the closest

The formula, by the way, can be used to find the diagonal of a similar situation in the 4D. (You just need to add another dimension squared)