Year 9 Interactive Maths - Second Edition

Pythagoras' Theorem in Three Dimensions

A three-dimensional object can be described by three measurements - length, width and height.

We can use Pythagoras' Theorem to find the length of the longest straw that will fit inside the box or cylinder.

Example 21

A can of drink is in the shape of a cylinder with height 15 cm and radius 4 cm.  What is the length of the longest straw that will fit inside the can?

Solution:

Let the length of the straw be x cm.

So, the length of the longest straw that will fit inside the can is 17 cm.