

1
— 
Construct
square A drawn to scale. 


2
— 
Calculate
the distance of 17cm from the middle of square A base downwards.
Determine point a. 


3
— 
In the upward direction, draw a vertical line of 1.70m from bottom
to top of point a and mark point b. 


4
— 
Construct
a square with the same dimensions of square A on the
line constructed between points a and b. See
square B in figure 4.



5
— 
Draw
a horizontal line crossing the two squares at point b height. 


6
— 
Draw
a diagonal line from point c to point d (see figure
4). 


7
— 
From
the vertices of square A, draw lines that vanish in point
b. 


8
— 
Determine
point f at the intersection of the lines that join points
e, b, c and d. 


9
— 
By joining
points f and g with a horizontal line we will
have a horizontal plane.


