Name: Krista Bischoff
Who is asking: Student
I can't get the picture to copy to this form so I guess I will have to try and describe the picture the best that I can. The top right hand corner is folded to the left side, almost half way down. The width of the paper is a ( the width of the bottom part which is not folded.) The creased side is L and the part shorter part of the folded area is x (the part that would have been the top right of the original piece.)
I hope that this is good enough for you to understand.Hi Krista,
In the diagram below the point P is folded to the point S leaving the "crease" QT of length L. PS is the line segment joing P and S.
Triangles PQU and QSU are congruent and thus angle QUP = angle SUQ. Since their sum is 180o they are each 90o angles. If angle QPU = angle USQ = a then angle PQU =angle UQS = 90o - a. Therefore angle SQR = 2a.
Using triangle SQR we see that
Using the fact that
we see that
Also from triangle PQT