Geometry Algorithms

  • French students imagine geometry diagrams and give their instructions. Killian Bunel takes the role of the secretary for his French peers.

    Can you draw their diagrams?

    2B drawing algorithms in geometry


    Name : Jean de Loynes d’Estrées  

    Let C be a circle of center O and radius 3. 

    Draw a line segment AB with midpoint O in green.   

    Draw a line segment DE perpendicular to AB and interseting line AB at center O in red.  

    Draw a line segment AD and BD in green.  

    Draw the circle of center E and radius 2.  

    Denote by F and G the points where the two circles intersect.  

    Draw the line d passing through F and G in red.  


    Name : Hélie SAIllARD, Mathias vivien 

    Let ABC be a right-angled triangle in black with a right angle in B 

    Denote by point F in blue in the mid point of AC 

    Draw in green the straight line d . passing throught points B and F 

    Let C be the circle in black of center F and radius FB  

    Let I be the circle in pink of center B and radius BF 

    Let J the circle in orange of center A and radius AF 


    Name : Evan Schryve

    Draw a square D.R.A.W  

    The périmeter of this square is 20cm  

    Draw th straight line DR (5 cm)  

    Denote by O the midpoint of this line segment DA  

    Draw the circle of centerpoint R  

    Radius 3cm  


    Name : Julyan Nourry

    Sketch a isosceles triangle KRB. 

    Sketch a parallel line to line segment RB, is called J. 

    Let be altitude from point R. 

    Draw a circle inside the isosceles triangle KRB radius 1.5 abd center D. 

    Consider a diameter with end points C and F. 


    Name :  Théo LOISEAUX--CACHARD 

    Let C be a circle of center O and radius 4. 

    Consider a diameter with end points A and B in green. 

    Draw in red the perpendicular line to line segment AB and passing through point O. 

    Let F and G be any points on this straight line in blue. 

    The straight line joining points F and G is denoted by FG. 

    Draw in black the triangle AFG. 


    Name : Martin PONTABRY 

    Sketch a straight line in green 

    Take the set squares

    Place your set square on the straight line  

    Sketch a straight line in red perpendicular at that first straight line  

    Name the straight (d) and (d’) 

    Place the symbol the perpendicular lines   


    Name : PARRET Ylane 

    Draw the straight-line D in green. 

    Draw any straight-line P perpendicular to line D in pink. 

    Line D and P intersect at point A in blue. 

    Draw the circle of center A di diameter 5cm in orange. 

    Let C be any point on the straight lines P in grey. 

    Let I be any point on the straight lines D in brown. 

    Draw the triangle C, A, I in yellow. 


    Name: Aymeric FINFE  

    1)First, Draw in black a line segment AB  

    2)Consider O the midpoint of line segment AB  

    3)Draw in black a line segment CO perpendicular to AB  

    4) Next, Draw in blue the line AC and in red the line BC  

    5)Draw in green the line DE parallele with AB passing through C  

    7) Draw the symmetric of this diagramm with respect to line segment AB 


    Name : MOREL Lucie 

    Let ABCD be a black rectangle of length 15cm and width 11cm 

    Let E be the midpoint of line segment ab 

    Let F be the midpoint of line segment BC 

    Let G be the midpoint of the line segment CD 

    Let H be the midpoint of line segment DA 

    Draw in green the quadrilateral EFGH  

    Draw in red line segment HF 

    Draw in red line segment EG 

    Diagonals of quadrilateral EFGH intersect at point I 


    Name : PIRON Mathias 

    draw in a red straight line joining two point A and B 

    drawin gray the circle with center A and radius 3  

    consider any point M on this circle  

    draw the line between A M 

    draw in  green the line segment B M 

    draw in gray the circle center M and passing through point 



    Name : RICHARD Clément 


    -draw in green a line segment UY, of length 5 centimeter, 

    -draw in green a line segment GU perpendicular to UY, of 5 centimeter, 

    -draw in red the straight line GY, 

    -consider the right-angled triangle GUY 

    -draw in green a straight line YS perpendicular to YU, of 5 centimeter, 

    -draw in green a straight line GS parallel to UY, of 5 centimeter 

    -consider the square GUYS 


    Name : Adam CHRISTIEN 

    Let O be a circle of center A, in grey and radius 4,1 cm 

    Consider any point B on circle O 

    Straight line AB is called d and is in red 

    Consider any other point C on circle O 

    Straight line AC is called d’ and in green 

    Sraight line CB is called d’’ in grey 

    ABC is an isosceles tringle 


    Name : Damien Pasquer  

    (All parallel lines segments have the same length in the driagram described below) 

    Draw in brown 2 parallel lines segments AB and CD of length 0.5cm and 2 cm apart 

    Add point A and C arethe top and B and C the bottom of the segment 

    Draw in green the line segment AC  

    Draw in green half circle of diameter AC 

    Add a point E of segment AC  

    Do parallel line CE with 0.2cm apart in brown 

    Add point F to top right of the parallel  

    Draw a half circle of FE in brown 



    Take a compass and draw a circle of radius 1.5.

    Let A be the center point, in yellow.

    Take a pen and draw another point at distance 10 cm from A.

    This point is denoted by B. Draw, in blue, the circle of center B and radius 1.5 cm.

    Draw in pink, rectangle ABCD with a length equal AB and width equal to 2.5.

    Let E be the point an line segment CD, at a distance from C equal to 2.

    Repeat the preceding process for point F at a distance from D equal to 3.

    And finally, draw in green rectangle EFGH with a width equal to 1.5.