#lang racket (require (planet wcy/mpost-wrapper)) (provide main) (define (main) (let ((A (point 0 0)) (B (point '3cm 0)) (C (point '1cm '2cm)) (O (unknown-point))) (define (f B C) (eqn= (op- O (mediation 1/2 B C)) (op* (whatever) (rotate 90 (op- B C))))) (f B C) (f A B) (draw (op-- A B C 'cycle)) (draw O #:withpen (scale '4bp 'pencircle)) (draw (fullcircle (op* 2 (op-abs (op- O A))) O))))