Here I just make and upload not very wonderful pictures to try and help out with what I write on en.wikipedia.

You can find my wiki persona there at [User:Dmcq].

Sprung floor: Basketweave

Sprung floor: Low profile

Haga theorem 1

Construction of cube root of 2 using origami

Trisecting an angle using origami

Illustration of Maekawas Theorem number of valley's and folds differs by 2 at a point

Crease pattern for 25 point sea urchin type solution for Napkin folding problem

Crease pattern for an example Miura-ori

Smart waterbomb - circular base and curved folds

Selfridge-Conway fair division

stromquist moving-knife procedure

Math MOS geometry illustration

Illustrate what the hypotenuse is

Codomain of a function (updated from Damien Karras)

Principal value of the arg function

circle with some values of atan2

Deriviative of exponential function equals the function

Euclid bk1 prop5 pons asinorum, greek letters

Euclid bk1 prop5 pons asinorum, english letters

Multiplication example 4 bags of three coloured marbles

Area of field by multiplication

Multiplication: Two scaled by 3 produces 6

A proof without words for the pizza theorem

A proof without words for Nicomachus's theorem

Area of annulus determined by tangent length

Basic idea of Mamikon's theorem

Finding the area of a cycloid using Mamikon's theorem

Solving polynomials using Lill's method

Solution of ax^{2}+bx+c using Lill's method. Solutions are −AX1/SA, −AX2/SA

Antiparallelogram linkage with bracing to not turn into a parallelogram

Sylvester's Link Fan or Isoklinstat to trisect angles

Spherical coordinate system with a common maths convention opposite to that in physics

Penrose tiling of gingerbread men

Penrose tiling like a Roman floor

Perspective projection of a tesseract with hidden vertex elimination.

Tesseract with hidden volume elimination showing nearest point (updated from Tetracube)

Demonstrate that the projection of a square can be concave

Normalized IQ distribution mean 100 and standard deviation 15