Points and Lines on Folded Paper

A

B

C

D

line AB

line CD

paper position

show creases

save crease

delete creases

Drag the locator to fold the piece of piece of A4 paper, which is yellow on one side and light blue on the other. You can add points

A

,

B

,

C

or

D

using the 2D sliders on the left. Vary these controls to verify Huzita's axioms.