This may require some effort. try and drag the red points to make the triangle below be 45-45-90 or the sides as 3-4-5 or some multiple...

Notice the ratio measurement as....

All 45-45-90 rt triangles have r = 12 + 8sqrt(2) = 23.3

and

All 3-4-5 (6-8-10) rt. triangles have r = 24

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