Folded over
A rectangular piece of paper is folded. Can you work out one of the lengths in the diagram?
Age
14 to 16
Challenge level
Problem
Image
A rectangular sheet of paper with sides $1$ and $ \sqrt{2} $ has been folded once as shown, so that one corner just meets the opposite long edge. What is the value of the length $d$?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Student Solutions
Image
The fold is made along $BE$. $A$ folds onto $A^{\prime}$.