>>425773one more comment on 5)
you assumed some bullshit right angles
the tangents are perpendicular to the radii and the bisectors are perpendicular to the chords
that should be all
>>4257867) this is the pulley problem
you have the 'stretched' belt length, but now you need the arc lengths where the belt touches the circles
https://undergroundmathematics.org/circles/belt/solution8) note that two radii make one side length a triangle
the hexagon is made of six equilateral triangles, each with side length 20mm
there are three-sixths of a circle in each triangle
find the height of one triangle
then find the area of triangle
then subtract the area of one triangle covered by the three circle slices
multiply by six for the total uncovered area
