the answer would be 6 planes
South west
Shifting 4 units left (decreasing in x-axis by 4 units)
Shifting 5 units down (decreasing in y-axis by 5 units)
Apply to every vertices coordinates(x - 4, y - 5)
New coordinates
A(-2, -1)
B(-1, -4)
C(1,0)
let the line between 2 tria be y
sin 60/8√2 = sin 90/y
y=13.06
sin 45/13.06 = sin 90/x
x=18.46
The answer is Vertical angles are equal.
