You can drag points A, B, C and D in this example. EF=GH and they are parallel.
Although EG and FH are perpendicular here, this is not true in general.
Level 1: Construct an equilateral triangle
Rigid Motions: Question 4
Non-bijective functions and inverses
المساحة بين منحنيين
Parallel Lines & Angles
Exploration 2 - Proportionallity with 3 Lines
Vector Field 3D